From 146f1d1c83abbd98beca8e82e04db62fc135e51e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johel=20Ernesto=20Guerrero=20Pe=C3=B1a?=
 <johelegp@gmail.com>
Date: Mon, 28 Mar 2022 10:17:46 -0400
Subject: [PATCH 01/68] fix: improve downcast mode off

---
 src/core/include/units/quantity.h             |  39 ++---
 src/core/include/units/quantity_kind.h        |  15 +-
 test/unit_test/static/chrono_test.cpp         |  13 +-
 test/unit_test/static/kind_test.cpp           |  13 +-
 test/unit_test/static/quantity_kind_test.cpp  | 136 +++++++++---------
 .../static/quantity_point_kind_test.cpp       |  80 +++++------
 test/unit_test/static/quantity_test.cpp       |  76 +++++-----
 test/unit_test/static/references_test.cpp     |   5 +-
 test/unit_test/static/test_tools.h            |  11 +-
 9 files changed, 196 insertions(+), 192 deletions(-)

diff --git a/src/core/include/units/quantity.h b/src/core/include/units/quantity.h
index 9eb2722b..39c3c805 100644
--- a/src/core/include/units/quantity.h
+++ b/src/core/include/units/quantity.h
@@ -45,6 +45,12 @@ inline constexpr auto make_quantity = [](auto&& v) {
   return quantity<typename decltype(R)::dimension, typename decltype(R)::unit, Rep>(std::forward<decltype(v)>(v));
 };
 
+template<typename T>
+concept quantity_one =
+  Quantity<T> &&
+  (std::same_as<typename T::dimension, dim_one> || std::same_as<typename T::dimension, unknown_dimension<>>) &&
+  detail::equivalent_unit<typename T::unit, typename T::dimension, ::units::one, typename T::dimension>::value;
+
 }  // namespace detail
 
 template<typename T>
@@ -133,8 +139,7 @@ public:
 
   template<typename Value>
     requires(safe_convertible_to_<std::remove_cvref_t<Value>, rep>)
-  constexpr explicit(!(std::same_as<dimension, dim_one> && std::same_as<unit, ::units::one>)) quantity(Value&& v) :
-      number_(std::forward<Value>(v))
+  constexpr explicit(!detail::quantity_one<quantity>) quantity(Value&& v) : number_(std::forward<Value>(v))
   {
   }
 
@@ -252,9 +257,9 @@ public:
     number_ *= rhs;
     return *this;
   }
-  template<typename Rep2>
-  constexpr quantity& operator*=(const dimensionless<units::one, Rep2>& rhs)
-    requires requires(rep a, const Rep2 b) {
+  template<detail::quantity_one Q>
+  constexpr quantity& operator*=(const Q& rhs)
+    requires requires(rep a, const typename Q::rep b) {
                {
                  a *= b
                  } -> std::same_as<rep&>;
@@ -276,15 +281,15 @@ public:
     number_ /= rhs;
     return *this;
   }
-  template<typename Rep2>
-  constexpr quantity& operator/=(const dimensionless<units::one, Rep2>& rhs)
-    requires requires(rep a, const Rep2 b) {
+  template<detail::quantity_one Q>
+  constexpr quantity& operator/=(const Q& rhs)
+    requires requires(rep a, const typename Q::rep b) {
                {
                  a /= b
                  } -> std::same_as<rep&>;
              }
   {
-    gsl_ExpectsAudit(rhs.number() != quantity_values<Rep2>::zero());
+    gsl_ExpectsAudit(rhs.number() != quantity_values<typename Q::rep>::zero());
     number_ /= rhs.number();
     return *this;
   }
@@ -302,15 +307,15 @@ public:
     return *this;
   }
 
-  template<typename Rep2>
-  constexpr quantity& operator%=(const dimensionless<units::one, Rep2>& rhs)
-    requires(!floating_point_<rep>) && (!floating_point_<Rep2>) && requires(rep a, const Rep2 b) {
-                                                                     {
-                                                                       a %= b
-                                                                       } -> std::same_as<rep&>;
-                                                                   }
+  template<detail::quantity_one Q>
+  constexpr quantity& operator%=(const Q& rhs)
+    requires(!floating_point_<rep>) && (!floating_point_<typename Q::rep>) && requires(rep a, const typename Q::rep b) {
+                                                                                {
+                                                                                  a %= b
+                                                                                  } -> std::same_as<rep&>;
+                                                                              }
   {
-    gsl_ExpectsAudit(rhs.number() != quantity_values<Rep2>::zero());
+    gsl_ExpectsAudit(rhs.number() != quantity_values<typename Q::rep>::zero());
     number_ %= rhs.number();
     return *this;
   }
diff --git a/src/core/include/units/quantity_kind.h b/src/core/include/units/quantity_kind.h
index a4bcc594..a47fd547 100644
--- a/src/core/include/units/quantity_kind.h
+++ b/src/core/include/units/quantity_kind.h
@@ -54,6 +54,10 @@ inline constexpr auto downcasted_kind_fn = [](auto q) {
 template<QuantityKind QK>
 inline constexpr auto& downcasted_kind = downcasted_kind_fn<typename QK::kind_type::base_kind>;
 
+template<typename T, typename K>
+concept quantity_kind_one = QuantityKind<T> && equivalent<typename T::kind_type, downcast_kind<K, dim_one>> &&
+                            detail::quantity_one<typename T::quantity_type>;
+
 }  // namespace detail
 
 /**
@@ -198,8 +202,8 @@ public:
     q_ *= rhs;
     return *this;
   }
-  template<typename Rep2>
-  constexpr quantity_kind& operator*=(const quantity_kind<downcast_kind<K, dim_one>, units::one, Rep2>& rhs)
+  template<detail::quantity_kind_one<K> QK>
+  constexpr quantity_kind& operator*=(const QK& rhs)
     requires requires(quantity_type q) { q *= rhs.common(); }
   {
     q_ *= rhs.common();
@@ -214,8 +218,8 @@ public:
     q_ /= rhs;
     return *this;
   }
-  template<typename Rep2>
-  constexpr quantity_kind& operator/=(const quantity_kind<downcast_kind<K, dim_one>, units::one, Rep2>& rhs)
+  template<detail::quantity_kind_one<K> QK>
+  constexpr quantity_kind& operator/=(const QK& rhs)
     requires requires(quantity_type q) { q /= rhs.common(); }
   {
     q_ /= rhs.common();
@@ -233,8 +237,7 @@ public:
 
   template<QuantityKind QK>
   constexpr quantity_kind& operator%=(const QK& rhs)
-    requires(QuantityKindEquivalentTo<QK, quantity_kind> ||
-             std::same_as<typename QK::kind_type, downcast_kind<K, dim_one>>) &&
+    requires(QuantityKindEquivalentTo<QK, quantity_kind> || detail::quantity_kind_one<QK, K>) &&
             requires(quantity_type q) { q %= rhs.common(); }
   {
     gsl_ExpectsAudit(rhs.common().number() != quantity_values<typename QK::rep>::zero());
diff --git a/test/unit_test/static/chrono_test.cpp b/test/unit_test/static/chrono_test.cpp
index 348ec3ba..952ce1fa 100644
--- a/test/unit_test/static/chrono_test.cpp
+++ b/test/unit_test/static/chrono_test.cpp
@@ -20,6 +20,7 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
+#include "test_tools.h"
 #include <units/bits/external/type_traits.h>
 #include <units/chrono.h>
 #include <units/isq/si/length.h>
@@ -82,12 +83,12 @@ static_assert(!std::convertible_to<sys_seconds, time_point<std::chrono::system_c
 
 
 // CTAD
-static_assert(is_same_v<decltype(quantity{1s}), si::time<si::second, std::chrono::seconds::rep>>);
-static_assert(is_same_v<decltype(quantity{1h}), si::time<si::hour, std::chrono::hours::rep>>);
-static_assert(is_same_v<decltype(quantity_point{sys_seconds{1s}}),
-                        time_point<std::chrono::system_clock, si::second, sys_seconds::rep>>);
-static_assert(is_same_v<decltype(quantity_point{sys_days{sys_days::duration{1}}}),
-                        time_point<std::chrono::system_clock, si::day, sys_days::rep>>);
+static_assert(compare<decltype(quantity{1s}), si::time<si::second, std::chrono::seconds::rep>>);
+static_assert(compare<decltype(quantity{1h}), si::time<si::hour, std::chrono::hours::rep>>);
+static_assert(compare<decltype(quantity_point{sys_seconds{1s}}),
+                      time_point<std::chrono::system_clock, si::second, sys_seconds::rep>>);
+static_assert(compare<decltype(quantity_point{sys_days{sys_days::duration{1}}}),
+                      time_point<std::chrono::system_clock, si::day, sys_days::rep>>);
 
 // operators
 static_assert(quantity{1s} + 1_q_s == 2_q_s);
diff --git a/test/unit_test/static/kind_test.cpp b/test/unit_test/static/kind_test.cpp
index 3e9b4eb8..0c79059c 100644
--- a/test/unit_test/static/kind_test.cpp
+++ b/test/unit_test/static/kind_test.cpp
@@ -20,6 +20,7 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
+#include "test_tools.h"
 #include <units/bits/equivalent.h>
 #include <units/bits/external/downcasting.h>
 #include <units/bits/external/type_traits.h>
@@ -62,7 +63,7 @@ static_assert(!PointKind<azimuth::_kind_base>);
 
 static_assert(is_same_v<radius::base_kind, radius>);
 static_assert(is_same_v<radius::dimension, dim_length>);
-static_assert(is_same_v<downcast_result<radius>, downcast_kind<radius, dim_length>>);
+static_assert(compare<downcast_result<radius>, downcast_kind<radius, dim_length>>);
 
 static_assert(equivalent<radius, radius>);
 static_assert(equivalent<radius, radius::kind>);
@@ -124,7 +125,7 @@ static_assert(PointKind<abscissa::_point_kind_base>);
 
 static_assert(is_same_v<abscissa::base_kind, width>);
 static_assert(is_same_v<abscissa::dimension, dim_length>);
-static_assert(is_same_v<downcast_result<abscissa>, downcast_point_kind<width>>);
+static_assert(compare<downcast_result<abscissa>, downcast_point_kind<width>>);
 
 static_assert(equivalent<abscissa, abscissa>);
 static_assert(equivalent<abscissa, abscissa::point_kind>);
@@ -162,8 +163,8 @@ static_assert(!PointKind<rate_of_climb::_kind_base>);
 
 static_assert(is_same_v<rate_of_climb::base_kind, height>);
 static_assert(is_same_v<rate_of_climb::dimension, dim_speed>);
-static_assert(is_same_v<downcast_result<rate_of_climb>, downcast_kind<rate_of_climb, dim_speed>>);
-static_assert(is_same_v<downcast_result<rate_of_climb>, downcast_kind<height, dim_speed>>);
+static_assert(compare<downcast_result<rate_of_climb>, downcast_kind<rate_of_climb, dim_speed>>);
+static_assert(compare<downcast_result<rate_of_climb>, downcast_kind<height, dim_speed>>);
 
 static_assert(equivalent<rate_of_climb, rate_of_climb>);
 static_assert(equivalent<rate_of_climb, rate_of_climb::derived_kind>);
@@ -181,7 +182,7 @@ static_assert(PointKind<velocity_of_climb::_point_kind_base>);
 
 static_assert(is_same_v<velocity_of_climb::base_kind, rate_of_climb>);
 static_assert(is_same_v<velocity_of_climb::dimension, dim_speed>);
-static_assert(is_same_v<downcast_result<velocity_of_climb>, downcast_point_kind<rate_of_climb>>);
+static_assert(compare<downcast_result<velocity_of_climb>, downcast_point_kind<rate_of_climb>>);
 
 static_assert(equivalent<velocity_of_climb, velocity_of_climb>);
 static_assert(equivalent<velocity_of_climb, velocity_of_climb::point_kind>);
@@ -200,6 +201,6 @@ static_assert(!equivalent<height::_kind_base, velocity_of_climb::_point_kind_bas
 static_assert(!equivalent<rate_of_climb, velocity_of_climb>);
 static_assert(!equivalent<rate_of_climb::_kind_base, velocity_of_climb::_point_kind_base>);
 
-static_assert(is_same_v<downcast_result<height>, downcast_kind<rate_of_climb, dim_length>>);
+static_assert(compare<downcast_result<height>, downcast_kind<rate_of_climb, dim_length>>);
 
 }  // namespace
diff --git a/test/unit_test/static/quantity_kind_test.cpp b/test/unit_test/static/quantity_kind_test.cpp
index d9dc2961..c696c1ca 100644
--- a/test/unit_test/static/quantity_kind_test.cpp
+++ b/test/unit_test/static/quantity_kind_test.cpp
@@ -481,11 +481,11 @@ static_assert(invalid_compound_assignments_<time_kind, second, std::chrono::seco
 static_assert(same(width<metre, int>(2 * m) + width<metre, int>(3 * m), width<metre, int>(5 * m)));
 static_assert(same(width<metre, int>(2 * m) + width<metre, double>(3. * m), width<metre, double>(5. * m)));
 static_assert(same(width<metre, double>(2. * m) + width<metre, int>(3 * m), width<metre, double>(5. * m)));
-static_assert(same(width<kilometre, int>(2 * km) + width<metre, double>(3e3 * m), width<metre, double>(5e3 * m)));
+static_assert(comp(width<kilometre, int>(2 * km) + width<metre, double>(3e3 * m), width<metre, double>(5e3 * m)));
 static_assert(same(width<metre, int>(2 * m) - width<metre, int>(3 * m), width<metre, int>(-1 * m)));
 static_assert(same(width<metre, int>(2 * m) - width<metre, double>(3. * m), width<metre, double>(-1. * m)));
 static_assert(same(width<metre, double>(2. * m) - width<metre, int>(3 * m), width<metre, double>(-1. * m)));
-static_assert(same(width<metre, double>(2e3 * m) - width<kilometre, int>(3 * km), width<metre, double>(-1e3 * m)));
+static_assert(comp(width<metre, double>(2e3 * m) - width<kilometre, int>(3 * km), width<metre, double>(-1e3 * m)));
 
 static_assert(
   is_same_v<decltype((width<metre, std::uint8_t>(0 * m) + width<metre, std::uint8_t>(0 * m)).common().number()),
@@ -531,131 +531,131 @@ static_assert(same(2 * width<metre, int>(3 * m), width<metre, int>(6 * m)));
 static_assert(same(2 * width<metre, double>(3. * m), width<metre, double>(6. * m)));
 static_assert(same(2. * width<metre, int>(3 * m), width<metre, double>(6. * m)));
 
-static_assert(same(width<metre, int>(2 * m) * quantity(3), width<metre, int>(6 * m)));
-static_assert(same(width<metre, int>(2 * m) * quantity(3.), width<metre, double>(6. * m)));
-static_assert(same(width<metre, double>(2. * m) * quantity(3), width<metre, double>(6. * m)));
-static_assert(same(quantity(2) * width<metre, int>(3 * m), width<metre, int>(6 * m)));
-static_assert(same(quantity(2) * width<metre, double>(3. * m), width<metre, double>(6. * m)));
-static_assert(same(quantity(2.) * width<metre, int>(3 * m), width<metre, double>(6. * m)));
+static_assert(comp(width<metre, int>(2 * m) * quantity(3), width<metre, int>(6 * m)));
+static_assert(comp(width<metre, int>(2 * m) * quantity(3.), width<metre, double>(6. * m)));
+static_assert(comp(width<metre, double>(2. * m) * quantity(3), width<metre, double>(6. * m)));
+static_assert(comp(quantity(2) * width<metre, int>(3 * m), width<metre, int>(6 * m)));
+static_assert(comp(quantity(2) * width<metre, double>(3. * m), width<metre, double>(6. * m)));
+static_assert(comp(quantity(2.) * width<metre, int>(3 * m), width<metre, double>(6. * m)));
 
-static_assert(same(width<metre, int>(2 * m) * quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(3),
+static_assert(comp(width<metre, int>(2 * m) * quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(3),
                    width<metre, int>(6 * m)));
-static_assert(same(width<metre, int>(2 * m) * quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(3.),
+static_assert(comp(width<metre, int>(2 * m) * quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(3.),
                    width<metre, double>(6. * m)));
-static_assert(same(width<metre, double>(2. * m) * quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(3),
+static_assert(comp(width<metre, double>(2. * m) * quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(3),
                    width<metre, double>(6. * m)));
-static_assert(same(quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(2) * width<metre, int>(3 * m),
+static_assert(comp(quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(2) * width<metre, int>(3 * m),
                    width<metre, int>(6 * m)));
-static_assert(same(quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(2) * width<metre, double>(3. * m),
+static_assert(comp(quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(2) * width<metre, double>(3. * m),
                    width<metre, double>(6. * m)));
-static_assert(same(quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(2.) * width<metre, int>(3 * m),
+static_assert(comp(quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(2.) * width<metre, int>(3 * m),
                    width<metre, double>(6. * m)));
 
-static_assert(same(height<metre, int>(2 * m) * (3 * Hz), rate_of_climb<metre_per_second, int>(6 * (m / s))));
-static_assert(same(height<metre, int>(2 * m) * (3. * Hz), rate_of_climb<metre_per_second, double>(6. * (m / s))));
-static_assert(same(height<metre, double>(2. * m) * (3 * Hz), rate_of_climb<metre_per_second, double>(6. * (m / s))));
-static_assert(same((2 * Hz) * height<metre, int>(3 * m), rate_of_climb<metre_per_second, int>(6 * (m / s))));
-static_assert(same((2 * Hz) * height<metre, double>(3. * m), rate_of_climb<metre_per_second, double>(6. * (m / s))));
-static_assert(same((2. * Hz) * height<metre, int>(3 * m), rate_of_climb<metre_per_second, double>(6. * (m / s))));
+static_assert(comp(height<metre, int>(2 * m) * (3 * Hz), rate_of_climb<metre_per_second, int>(6 * (m / s))));
+static_assert(comp(height<metre, int>(2 * m) * (3. * Hz), rate_of_climb<metre_per_second, double>(6. * (m / s))));
+static_assert(comp(height<metre, double>(2. * m) * (3 * Hz), rate_of_climb<metre_per_second, double>(6. * (m / s))));
+static_assert(comp((2 * Hz) * height<metre, int>(3 * m), rate_of_climb<metre_per_second, int>(6 * (m / s))));
+static_assert(comp((2 * Hz) * height<metre, double>(3. * m), rate_of_climb<metre_per_second, double>(6. * (m / s))));
+static_assert(comp((2. * Hz) * height<metre, int>(3 * m), rate_of_climb<metre_per_second, double>(6. * (m / s))));
 
-static_assert(same(quantity_kind<time_kind, second, int>(2 * s) * (3 * Hz),
+static_assert(comp(quantity_kind<time_kind, second, int>(2 * s) * (3 * Hz),
                    quantity_kind<downcast_kind<time_kind, dim_one>, one, int>(6)));
-static_assert(same((3 * Hz) * quantity_kind<time_kind, second, int>(2 * s),
+static_assert(comp((3 * Hz) * quantity_kind<time_kind, second, int>(2 * s),
                    quantity_kind<downcast_kind<time_kind, dim_one>, one, int>(6)));
 
-static_assert(same(apples<one, int>(2) * quantity(2), apples<one, int>(4)));
-static_assert(same(quantity(2) * apples<one, int>(2), apples<one, int>(4)));
+static_assert(comp(apples<one, int>(2) * quantity(2), apples<one, int>(4)));
+static_assert(comp(quantity(2) * apples<one, int>(2), apples<one, int>(4)));
 
 // clang-format off
-static_assert(same(width<metre, int>(4 * m) * (1 * m), horizontal_area<square_metre, int>(4 * (m * m))));
-static_assert(same(width<metre, int>(2 * m) * width<metre, int>(2 * m), horizontal_area<square_metre, int>(4 * (m * m))));
-static_assert(same(width<metre, int>(2 * m) * width<metre, double>(2 * m), horizontal_area<square_metre, double>(4 * (m * m))));
-static_assert(same(width<metre, double>(2 * m) * width<metre, int>(2 * m), horizontal_area<square_metre, double>(4 * (m * m))));
+static_assert(comp(width<metre, int>(4 * m) * (1 * m), horizontal_area<square_metre, int>(4 * (m * m))));
+static_assert(comp(width<metre, int>(2 * m) * width<metre, int>(2 * m), horizontal_area<square_metre, int>(4 * (m * m))));
+static_assert(comp(width<metre, int>(2 * m) * width<metre, double>(2 * m), horizontal_area<square_metre, double>(4 * (m * m))));
+static_assert(comp(width<metre, double>(2 * m) * width<metre, int>(2 * m), horizontal_area<square_metre, double>(4 * (m * m))));
 // clang-format on
 
-static_assert(same(apples<one, int>(2) * apples<one, int>(2), apples<one, int>(4)));
-static_assert(same(apples<one, int>(2) * (2 / apples<one, int>(1)), apples<one, int>(4)));
+static_assert(comp(apples<one, int>(2) * apples<one, int>(2), apples<one, int>(4)));
+static_assert(comp(apples<one, int>(2) * (2 / apples<one, int>(1)), apples<one, int>(4)));
 
-static_assert(same(width<kilometre>(4 * m) * (1 * mm), horizontal_area<square_metre>(4 * (m * mm))));
-static_assert(same(width<kilometre>(2 * m) * width<millimetre>(2 * m), horizontal_area<square_metre>(4 * (m * m))));
-static_assert(same(width<metre>(2 * m) * (1 / width<metre>(2 * m)),
+static_assert(comp(width<kilometre>(4 * m) * (1 * mm), horizontal_area<square_metre>(4 * (m * mm))));
+static_assert(comp(width<kilometre>(2 * m) * width<millimetre>(2 * m), horizontal_area<square_metre>(4 * (m * m))));
+static_assert(comp(width<metre>(2 * m) * (1 / width<metre>(2 * m)),
                    quantity_kind<downcast_kind<width_kind, dim_one>, one>(1)));
 
 static_assert(same(width<metre, int>(2 * m) / 3, width<metre, int>(0 * m)));
 static_assert(same(width<metre, int>(2 * m) / 3., width<metre, double>(2 / 3. * m)));
 static_assert(same(width<metre, double>(2. * m) / 3, width<metre, double>(2. / 3 * m)));
 
-static_assert(same(width<metre, int>(2 * m) / quantity(3), width<metre, int>(0 * m)));
-static_assert(same(width<metre, int>(2 * m) / quantity(3.), width<metre, double>(2 / 3. * m)));
-static_assert(same(width<metre, double>(2. * m) / quantity(3), width<metre, double>(2. / 3 * m)));
+static_assert(comp(width<metre, int>(2 * m) / quantity(3), width<metre, int>(0 * m)));
+static_assert(comp(width<metre, int>(2 * m) / quantity(3.), width<metre, double>(2 / 3. * m)));
+static_assert(comp(width<metre, double>(2. * m) / quantity(3), width<metre, double>(2. / 3 * m)));
 
-static_assert(same(width<metre, int>(2 * m) / quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(3),
+static_assert(comp(width<metre, int>(2 * m) / quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(3),
                    width<metre, int>(0 * m)));
-static_assert(same(width<metre, int>(2 * m) / quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(3.),
+static_assert(comp(width<metre, int>(2 * m) / quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(3.),
                    width<metre, double>(2 / 3. * m)));
-static_assert(same(width<metre, double>(2. * m) / quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(3),
+static_assert(comp(width<metre, double>(2. * m) / quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(3),
                    width<metre, double>(2. / 3 * m)));
 
-static_assert(same(2 / quantity_kind<time_kind, second, int>(3 * s),
+static_assert(comp(2 / quantity_kind<time_kind, second, int>(3 * s),
                    quantity_kind<downcast_kind<time_kind, dim_frequency>, hertz, int>(2 / 3 / (1 * s))));
-static_assert(same(2 / quantity_kind<time_kind, second, double>(3. * s),
+static_assert(comp(2 / quantity_kind<time_kind, second, double>(3. * s),
                    quantity_kind<downcast_kind<time_kind, dim_frequency>, hertz, double>(2 / 3. / (1 * s))));
-static_assert(same(2. / quantity_kind<time_kind, second, int>(3 * s),
+static_assert(comp(2. / quantity_kind<time_kind, second, int>(3 * s),
                    quantity_kind<downcast_kind<time_kind, dim_frequency>, hertz, double>(2 / 3. / (1 * s))));
 
-static_assert(same(quantity(2) / quantity_kind<time_kind, second, int>(3 * s),
+static_assert(comp(quantity(2) / quantity_kind<time_kind, second, int>(3 * s),
                    quantity_kind<downcast_kind<time_kind, dim_frequency>, hertz, int>(2 / 3 / (1 * s))));
-static_assert(same(quantity(2) / quantity_kind<time_kind, second, double>(3. * s),
+static_assert(comp(quantity(2) / quantity_kind<time_kind, second, double>(3. * s),
                    quantity_kind<downcast_kind<time_kind, dim_frequency>, hertz, double>(2 / 3. / (1 * s))));
-static_assert(same(quantity(2.) / quantity_kind<time_kind, second, int>(3 * s),
+static_assert(comp(quantity(2.) / quantity_kind<time_kind, second, int>(3 * s),
                    quantity_kind<downcast_kind<time_kind, dim_frequency>, hertz, double>(2 / 3. / (1 * s))));
 
-static_assert(same(quantity_kind<downcast_kind<time_kind, dim_one>, one, int>(2) /
+static_assert(comp(quantity_kind<downcast_kind<time_kind, dim_one>, one, int>(2) /
                      quantity_kind<time_kind, second, int>(3 * s),
                    quantity_kind<downcast_kind<time_kind, dim_frequency>, hertz, int>(2 / 3 / (1 * s))));
-static_assert(same(quantity_kind<downcast_kind<time_kind, dim_one>, one, int>(2) /
+static_assert(comp(quantity_kind<downcast_kind<time_kind, dim_one>, one, int>(2) /
                      quantity_kind<time_kind, second, double>(3. * s),
                    quantity_kind<downcast_kind<time_kind, dim_frequency>, hertz, double>(2 / 3. / (1 * s))));
-static_assert(same(quantity_kind<downcast_kind<time_kind, dim_one>, one, double>(2.) /
+static_assert(comp(quantity_kind<downcast_kind<time_kind, dim_one>, one, double>(2.) /
                      quantity_kind<time_kind, second, int>(3 * s),
                    quantity_kind<downcast_kind<time_kind, dim_frequency>, hertz, double>(2 / 3. / (1 * s))));
 
-static_assert(same(height<metre, int>(2 * m) / (3 * s), rate_of_climb<metre_per_second, int>(0 * (m / s))));
-static_assert(same(height<metre, int>(2 * m) / (3. * s), rate_of_climb<metre_per_second, double>(2 / 3. * (m / s))));
-static_assert(same(height<metre, double>(2. * m) / (3 * s), rate_of_climb<metre_per_second, double>(2. / 3 * (m / s))));
+static_assert(comp(height<metre, int>(2 * m) / (3 * s), rate_of_climb<metre_per_second, int>(0 * (m / s))));
+static_assert(comp(height<metre, int>(2 * m) / (3. * s), rate_of_climb<metre_per_second, double>(2 / 3. * (m / s))));
+static_assert(comp(height<metre, double>(2. * m) / (3 * s), rate_of_climb<metre_per_second, double>(2. / 3 * (m / s))));
 
-static_assert(same(width<metre, int>(2 * m) * dimensionless<percent, int>(3), width<centimetre, int>(6 * cm)));
-static_assert(same(dimensionless<percent, int>(2) * width<metre, int>(3 * m), width<centimetre, int>(6 * cm)));
-static_assert(same(width<metre, int>(2 * m) / dimensionless<percent, double>(3),
+static_assert(comp(width<metre, int>(2 * m) * dimensionless<percent, int>(3), width<centimetre, int>(6 * cm)));
+static_assert(comp(dimensionless<percent, int>(2) * width<metre, int>(3 * m), width<centimetre, int>(6 * cm)));
+static_assert(comp(width<metre, int>(2 * m) / dimensionless<percent, double>(3),
                    width<hectometre, double>(2. / 3 * hm)));
 static_assert(same(width<metre, int>(2 * m) % dimensionless<percent, int>(3), width<metre, int>(2 * m)));
 
-static_assert(same(height<metre, int>(2 * m) / (3 * m),
+static_assert(comp(height<metre, int>(2 * m) / (3 * m),
                    quantity_kind<downcast_kind<height_kind, dim_one>, one, int>(0)));
-static_assert(same(height<metre, int>(2 * m) / (3. * m),
+static_assert(comp(height<metre, int>(2 * m) / (3. * m),
                    quantity_kind<downcast_kind<height_kind, dim_one>, one, double>(2 / 3.)));
-static_assert(same(height<metre, double>(2. * m) / (3 * m),
+static_assert(comp(height<metre, double>(2. * m) / (3 * m),
                    quantity_kind<downcast_kind<height_kind, dim_one>, one, double>(2. / 3)));
 
-static_assert(same((2 * m) / height<metre, int>(3 * m),
+static_assert(comp((2 * m) / height<metre, int>(3 * m),
                    quantity_kind<downcast_kind<height_kind, dim_one>, one, int>(0)));
-static_assert(same((2 * m) / height<metre, double>(3. * m),
+static_assert(comp((2 * m) / height<metre, double>(3. * m),
                    quantity_kind<downcast_kind<height_kind, dim_one>, one, double>(2 / 3.)));
-static_assert(same((2. * m) / height<metre, int>(3 * m),
+static_assert(comp((2. * m) / height<metre, int>(3 * m),
                    quantity_kind<downcast_kind<height_kind, dim_one>, one, double>(2. / 3)));
 
-static_assert(same(width<metre, int>(8 * m) / width<metre, int>(2 * m),
+static_assert(comp(width<metre, int>(8 * m) / width<metre, int>(2 * m),
                    quantity_kind<downcast_kind<width_kind, dim_one>, one, int>(4)));
-static_assert(same(width<metre, int>(8 * m) / width<metre, double>(2 * m),
+static_assert(comp(width<metre, int>(8 * m) / width<metre, double>(2 * m),
                    quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(4.0)));
-static_assert(same(width<metre, double>(8 * m) / width<metre, int>(2 * m),
+static_assert(comp(width<metre, double>(8 * m) / width<metre, int>(2 * m),
                    quantity_kind<downcast_kind<width_kind, dim_one>, one, double>(4.0)));
 
-static_assert(same(apples<one, int>(8) / apples<one, int>(2), apples<one, int>(4)));
-static_assert(same(apples<one, int>(8) / (2 / apples<one, int>(1)), apples<one, int>(4)));
+static_assert(comp(apples<one, int>(8) / apples<one, int>(2), apples<one, int>(4)));
+static_assert(comp(apples<one, int>(8) / (2 / apples<one, int>(1)), apples<one, int>(4)));
 
-static_assert(same(horizontal_area<square_metre>(8 * (m * m)) / width<metre>(2 * m), width<metre>(4 * m)));
-static_assert(same(horizontal_area<square_metre>(4 * (m * m)) / (1 * m), width<metre>(4 * m)));
+static_assert(comp(horizontal_area<square_metre>(8 * (m * m)) / width<metre>(2 * m), width<metre>(4 * m)));
+static_assert(comp(horizontal_area<square_metre>(4 * (m * m)) / (1 * m), width<metre>(4 * m)));
 
 static_assert(same(width<metre, int>(2 * m) % 3, width<metre, int>(2 * m)));
 static_assert(same(width<metre, int>(3 * m) % width<metre, int>(2 * m), width<metre, int>(1 * m)));
@@ -800,7 +800,7 @@ static_assert(same(quantity_kind_cast<cgs_width_kind>(width<centimetre, int>(1 *
 static_assert(same(quantity_kind_cast<cgs_width_kind, cgs::centimetre>(width<centimetre, int>(1 * cm)), cgs_width<cgs::centimetre, int>(1 * cgs_cm)));
 static_assert(same(quantity_kind_cast<cgs_width_kind>(width<metre, int>(1 * m)), cgs_width<metre, int>(1 * m)));
 static_assert(same(quantity_kind_cast<cgs_width_kind, metre>(width<metre, int>(1 * m)), cgs_width<metre, int>(1 * m)));
-static_assert(same(quantity_kind_cast<cgs::dim_length>(width<centimetre, int>(1 * cm)), width<cgs::centimetre, int>(1 * cgs_cm)));
+static_assert(comp(quantity_kind_cast<cgs::dim_length>(width<centimetre, int>(1 * cm)), width<cgs::centimetre, int>(1 * cgs_cm)));
 static_assert(same(quantity_kind_cast<length<kilometre, int>>(width<metre, int>(1 * m)), width<kilometre, int>(0 * km)));
 static_assert(same(quantity_kind_cast<length<centimetre, int>>(width<metre, int>(1 * m)), width<centimetre, int>(100 * cm)));
 static_assert(same(quantity_kind_cast<length<centimetre, int>>(width<metre, double>(0.01 * m)), width<centimetre, int>(1 * cm)));
diff --git a/test/unit_test/static/quantity_point_kind_test.cpp b/test/unit_test/static/quantity_point_kind_test.cpp
index ab6e3cb6..f8febd8e 100644
--- a/test/unit_test/static/quantity_point_kind_test.cpp
+++ b/test/unit_test/static/quantity_point_kind_test.cpp
@@ -250,7 +250,7 @@ static_assert(abscissa<metre>{}.relative().common() == 0 * m);
 // CTAD
 /////////
 
-static_assert(same(quantity_point_kind(width<metre, int>(0 * m)), abscissa<metre, int>{}));
+static_assert(comp(quantity_point_kind(width<metre, int>(0 * m)), abscissa<metre, int>{}));
 static_assert(same(quantity_point_kind(abscissa<metre, int>(0 * m)), abscissa<metre, int>{}));
 
 
@@ -500,16 +500,16 @@ static_assert(invalid_compound_assignments_<time_point_kind, second, std::chrono
 /////////////////////////
 
 // clang-format off
-static_assert(same(abscissa<metre, int>(2 * m) + width<metre, int>(3 * m), abscissa<metre, int>(5 * m)));
-static_assert(same(abscissa<metre, int>(2 * m) + width<metre, double>(3. * m), abscissa<metre, double>(5. * m)));
-static_assert(same(abscissa<metre, double>(2. * m) + width<metre, int>(3 * m), abscissa<metre, double>(5. * m)));
-static_assert(same(abscissa<kilometre, int>(2 * km) + width<metre, double>(3e3 * m), abscissa<metre, double>(5e3 * m)));
-static_assert(same(abscissa<metre, double>(2e3 * m) + width<kilometre, int>(3 * km), abscissa<metre, double>(5e3 * m)));
-static_assert(same(width<metre, int>(2 * m) + abscissa<metre, int>(3 * m), abscissa<metre, int>(5 * m)));
-static_assert(same(width<metre, int>(2 * m) + abscissa<metre, double>(3. * m), abscissa<metre, double>(5. * m)));
-static_assert(same(width<metre, double>(2. * m) + abscissa<metre, int>(3 * m), abscissa<metre, double>(5. * m)));
-static_assert(same(width<kilometre, int>(2 * km) + abscissa<metre, double>(3e3 * m), abscissa<metre, double>(5e3 * m)));
-static_assert(same(width<metre, double>(2e3 * m) + abscissa<kilometre, int>(3 * km), abscissa<metre, double>(5e3 * m)));
+static_assert(comp(abscissa<metre, int>(2 * m) + width<metre, int>(3 * m), abscissa<metre, int>(5 * m)));
+static_assert(comp(abscissa<metre, int>(2 * m) + width<metre, double>(3. * m), abscissa<metre, double>(5. * m)));
+static_assert(comp(abscissa<metre, double>(2. * m) + width<metre, int>(3 * m), abscissa<metre, double>(5. * m)));
+static_assert(comp(abscissa<kilometre, int>(2 * km) + width<metre, double>(3e3 * m), abscissa<metre, double>(5e3 * m)));
+static_assert(comp(abscissa<metre, double>(2e3 * m) + width<kilometre, int>(3 * km), abscissa<metre, double>(5e3 * m)));
+static_assert(comp(width<metre, int>(2 * m) + abscissa<metre, int>(3 * m), abscissa<metre, int>(5 * m)));
+static_assert(comp(width<metre, int>(2 * m) + abscissa<metre, double>(3. * m), abscissa<metre, double>(5. * m)));
+static_assert(comp(width<metre, double>(2. * m) + abscissa<metre, int>(3 * m), abscissa<metre, double>(5. * m)));
+static_assert(comp(width<kilometre, int>(2 * km) + abscissa<metre, double>(3e3 * m), abscissa<metre, double>(5e3 * m)));
+static_assert(comp(width<metre, double>(2e3 * m) + abscissa<kilometre, int>(3 * km), abscissa<metre, double>(5e3 * m)));
 static_assert(!std::is_invocable_v<std::plus<>, abscissa<metre>, double>);
 static_assert(!std::is_invocable_v<std::plus<>, abscissa<metre>, length<metre>>);
 static_assert(!std::is_invocable_v<std::plus<>, abscissa<metre>, quantity_point<dynamic_origin<dim_length>, metre>>);
@@ -522,16 +522,16 @@ static_assert(!std::is_invocable_v<std::plus<>, quantity_point<dynamic_origin<di
 static_assert(!std::is_invocable_v<std::plus<>, length<metre>, abscissa<metre>>);
 static_assert(!std::is_invocable_v<std::plus<>, double, abscissa<metre>>);
 
-static_assert(same(abscissa<metre, int>(2 * m) - width<metre, int>(3 * m), abscissa<metre, int>(-1 * m)));
-static_assert(same(abscissa<metre, int>(2 * m) - width<metre, double>(3. * m), abscissa<metre, double>(-1. * m)));
-static_assert(same(abscissa<metre, double>(2. * m) - width<metre, int>(3 * m), abscissa<metre, double>(-1. * m)));
-static_assert(same(abscissa<kilometre, int>(2 * km) - width<metre, double>(3e3 * m), abscissa<metre, double>(-1e3 * m)));
-static_assert(same(abscissa<metre, double>(2e3 * m) - width<kilometre, int>(3 * km), abscissa<metre, double>(-1e3 * m)));
+static_assert(comp(abscissa<metre, int>(2 * m) - width<metre, int>(3 * m), abscissa<metre, int>(-1 * m)));
+static_assert(comp(abscissa<metre, int>(2 * m) - width<metre, double>(3. * m), abscissa<metre, double>(-1. * m)));
+static_assert(comp(abscissa<metre, double>(2. * m) - width<metre, int>(3 * m), abscissa<metre, double>(-1. * m)));
+static_assert(comp(abscissa<kilometre, int>(2 * km) - width<metre, double>(3e3 * m), abscissa<metre, double>(-1e3 * m)));
+static_assert(comp(abscissa<metre, double>(2e3 * m) - width<kilometre, int>(3 * km), abscissa<metre, double>(-1e3 * m)));
 static_assert(same(abscissa<metre, int>(2 * m) - abscissa<metre, int>(3 * m), width<metre, int>(-1 * m)));
 static_assert(same(abscissa<metre, int>(2 * m) - abscissa<metre, double>(3. * m), width<metre, double>(-1. * m)));
 static_assert(same(abscissa<metre, double>(2. * m) - abscissa<metre, int>(3 * m), width<metre, double>(-1. * m)));
-static_assert(same(abscissa<kilometre, int>(2 * km) - abscissa<metre, double>(3e3 * m), width<metre, double>(-1e3 * m)));
-static_assert(same(abscissa<metre, double>(2e3 * m) - abscissa<kilometre, int>(3 * km), width<metre, double>(-1e3 * m)));
+static_assert(comp(abscissa<kilometre, int>(2 * km) - abscissa<metre, double>(3e3 * m), width<metre, double>(-1e3 * m)));
+static_assert(comp(abscissa<metre, double>(2e3 * m) - abscissa<kilometre, int>(3 * km), width<metre, double>(-1e3 * m)));
 static_assert(!std::is_invocable_v<std::minus<>, abscissa<metre>, double>);
 static_assert(!std::is_invocable_v<std::minus<>, abscissa<metre>, length<metre>>);
 static_assert(!std::is_invocable_v<std::minus<>, abscissa<metre>, quantity_point<dynamic_origin<dim_length>, metre>>);
@@ -634,41 +634,41 @@ static_assert(same(quantity_point_kind_cast<abscissa<metre, double>>(abscissa<me
 static_assert(same(quantity_point_kind_cast<abscissa<kilometre, int>>(abscissa<metre, int>(999 * m)), abscissa<kilometre, int>(0 * km)));
 static_assert(same(quantity_point_kind_cast<abscissa<kilometre, int>>(abscissa<metre, int>(1000 * m)), abscissa<kilometre, int>(1 * km)));
 static_assert(same(quantity_point_kind_cast<abscissa<kilometre, double>>(abscissa<metre, int>(999 * m)), abscissa<kilometre, double>(0.999 * km)));
-static_assert(same(quantity_point_kind_cast<width<metre, int>>(abscissa<metre, int>(1 * m)), abscissa<metre, int>(1 * m)));
-static_assert(same(quantity_point_kind_cast<width<metre, double>>(abscissa<metre, int>(1 * m)), abscissa<metre, double>(1.0 * m)));
-static_assert(same(quantity_point_kind_cast<width<kilometre, int>>(abscissa<metre, int>(999 * m)), abscissa<kilometre, int>(0 * km)));
-static_assert(same(quantity_point_kind_cast<width<kilometre, int>>(abscissa<metre, int>(1000 * m)), abscissa<kilometre, int>(1 * km)));
-static_assert(same(quantity_point_kind_cast<width<kilometre, double>>(abscissa<metre, int>(999 * m)), abscissa<kilometre, double>(0.999 * km)));
-static_assert(same(quantity_point_kind_cast<double>(abscissa<metre, int>(1 * m)), abscissa<metre, double>(1.0 * m)));
-static_assert(same(quantity_point_kind_cast<metre>(abscissa<metre, int>(1 * m)), abscissa<metre, int>(1 * m)));
-static_assert(same(quantity_point_kind_cast<kilometre>(abscissa<metre, int>(999 * m)), abscissa<kilometre, int>(0 * km)));
-static_assert(same(quantity_point_kind_cast<kilometre>(abscissa<metre, int>(1000 * m)), abscissa<kilometre, int>(1 * km)));
+static_assert(comp(quantity_point_kind_cast<width<metre, int>>(abscissa<metre, int>(1 * m)), abscissa<metre, int>(1 * m)));
+static_assert(comp(quantity_point_kind_cast<width<metre, double>>(abscissa<metre, int>(1 * m)), abscissa<metre, double>(1.0 * m)));
+static_assert(comp(quantity_point_kind_cast<width<kilometre, int>>(abscissa<metre, int>(999 * m)), abscissa<kilometre, int>(0 * km)));
+static_assert(comp(quantity_point_kind_cast<width<kilometre, int>>(abscissa<metre, int>(1000 * m)), abscissa<kilometre, int>(1 * km)));
+static_assert(comp(quantity_point_kind_cast<width<kilometre, double>>(abscissa<metre, int>(999 * m)), abscissa<kilometre, double>(0.999 * km)));
+static_assert(comp(quantity_point_kind_cast<double>(abscissa<metre, int>(1 * m)), abscissa<metre, double>(1.0 * m)));
+static_assert(comp(quantity_point_kind_cast<metre>(abscissa<metre, int>(1 * m)), abscissa<metre, int>(1 * m)));
+static_assert(comp(quantity_point_kind_cast<kilometre>(abscissa<metre, int>(999 * m)), abscissa<kilometre, int>(0 * km)));
+static_assert(comp(quantity_point_kind_cast<kilometre>(abscissa<metre, int>(1000 * m)), abscissa<kilometre, int>(1 * km)));
 static_assert(same(quantity_point_kind_cast<ordinate<metre, int>>(abscissa<metre, int>(1 * m)), ordinate<metre, int>(1 * m)));
 static_assert(same(quantity_point_kind_cast<ordinate<metre, double>>(abscissa<metre, int>(1 * m)), ordinate<metre, double>(1.0 * m)));
 static_assert(same(quantity_point_kind_cast<ordinate<kilometre, int>>(abscissa<metre, int>(999 * m)), ordinate<kilometre, int>(0 * km)));
 static_assert(same(quantity_point_kind_cast<ordinate<kilometre, int>>(abscissa<metre, int>(1000 * m)), ordinate<kilometre, int>(1 * km)));
 static_assert(same(quantity_point_kind_cast<ordinate<kilometre, double>>(abscissa<metre, int>(999 * m)), ordinate<kilometre, double>(0.999 * km)));
-static_assert(same(quantity_point_kind_cast<height<metre, int>>(abscissa<metre, int>(1 * m)), ordinate<metre, int>(1 * m)));
-static_assert(same(quantity_point_kind_cast<height<metre, double>>(abscissa<metre, int>(1 * m)), ordinate<metre, double>(1.0 * m)));
-static_assert(same(quantity_point_kind_cast<height<kilometre, int>>(abscissa<metre, int>(999 * m)), ordinate<kilometre, int>(0 * km)));
-static_assert(same(quantity_point_kind_cast<height<kilometre, int>>(abscissa<metre, int>(1000 * m)), ordinate<kilometre, int>(1 * km)));
-static_assert(same(quantity_point_kind_cast<height<kilometre, double>>(abscissa<metre, int>(999 * m)), ordinate<kilometre, double>(0.999 * km)));
-static_assert(same(quantity_point_kind_cast<height_kind>(abscissa<metre, int>(1 * m)), ordinate<metre, int>(1 * m)));
+static_assert(comp(quantity_point_kind_cast<height<metre, int>>(abscissa<metre, int>(1 * m)), ordinate<metre, int>(1 * m)));
+static_assert(comp(quantity_point_kind_cast<height<metre, double>>(abscissa<metre, int>(1 * m)), ordinate<metre, double>(1.0 * m)));
+static_assert(comp(quantity_point_kind_cast<height<kilometre, int>>(abscissa<metre, int>(999 * m)), ordinate<kilometre, int>(0 * km)));
+static_assert(comp(quantity_point_kind_cast<height<kilometre, int>>(abscissa<metre, int>(1000 * m)), ordinate<kilometre, int>(1 * km)));
+static_assert(comp(quantity_point_kind_cast<height<kilometre, double>>(abscissa<metre, int>(999 * m)), ordinate<kilometre, double>(0.999 * km)));
+static_assert(comp(quantity_point_kind_cast<height_kind>(abscissa<metre, int>(1 * m)), ordinate<metre, int>(1 * m)));
 static_assert(same(quantity_point_kind_cast<ordinate_kind, metre>(abscissa<metre, int>(1 * m)), ordinate<metre, int>(1 * m)));
 static_assert(same(quantity_point_kind_cast<ordinate_kind, kilometre>(abscissa<metre, int>(999 * m)), ordinate<kilometre, int>(0 * km)));
 static_assert(same(quantity_point_kind_cast<ordinate_kind, kilometre>(abscissa<metre, int>(1000 * m)), ordinate<kilometre, int>(1 * km)));
 static_assert(same(quantity_point_kind_cast<cgs_width<cgs::centimetre, int>>(abscissa<centimetre, int>(1 * cm)), quantity_point_kind(cgs_width<cgs::centimetre, int>(1 * cgs_cm))));
 static_assert(same(quantity_point_kind_cast<cgs_width_kind>(abscissa<centimetre, int>(1 * cm)), quantity_point_kind(cgs_width<cgs::centimetre, int>(1 * cgs_cm))));
-static_assert(same(quantity_point_kind_cast<altitude_kind>(abscissa<centimetre, int>(1 * cm)), altitude<cgs::centimetre, int>(1 * cgs_cm)));
+static_assert(comp(quantity_point_kind_cast<altitude_kind>(abscissa<centimetre, int>(1 * cm)), altitude<cgs::centimetre, int>(1 * cgs_cm)));
 static_assert(same(quantity_point_kind_cast<altitude_kind, cgs::centimetre>(abscissa<centimetre, int>(1 * cm)), altitude<cgs::centimetre, int>(1 * cgs_cm)));
 static_assert(same(quantity_point_kind_cast<cgs_width_kind>(abscissa<metre, int>(1 * m)), quantity_point_kind(cgs_width<metre, int>(1 * m))));
-static_assert(same(quantity_point_kind_cast<altitude_kind>(abscissa<metre, int>(1 * m)), altitude<metre, int>(1 * m)));
+static_assert(comp(quantity_point_kind_cast<altitude_kind>(abscissa<metre, int>(1 * m)), altitude<metre, int>(1 * m)));
 static_assert(same(quantity_point_kind_cast<altitude_kind, metre>(abscissa<metre, int>(1 * m)), altitude<metre, int>(1 * m)));
-static_assert(same(quantity_point_kind_cast<cgs::dim_length>(abscissa<centimetre, int>(1 * cm)), abscissa<cgs::centimetre, int>(1 * cgs_cm)));
-static_assert(same(quantity_point_kind_cast<length<kilometre, int>>(abscissa<metre, int>(1 * m)), abscissa<kilometre, int>(0 * km)));
-static_assert(same(quantity_point_kind_cast<length<centimetre, int>>(abscissa<metre, int>(1 * m)), abscissa<centimetre, int>(100 * cm)));
-static_assert(same(quantity_point_kind_cast<length<centimetre, int>>(abscissa<metre, double>(0.01 * m)), abscissa<centimetre, int>(1 * cm)));
-static_assert(same(quantity_point_kind_cast<length<centimetre, int>>(abscissa<cgs::centimetre, int>(1 * cgs_cm)), abscissa<cgs::centimetre, int>(1 * cgs_cm)));
+static_assert(comp(quantity_point_kind_cast<cgs::dim_length>(abscissa<centimetre, int>(1 * cm)), abscissa<cgs::centimetre, int>(1 * cgs_cm)));
+static_assert(comp(quantity_point_kind_cast<length<kilometre, int>>(abscissa<metre, int>(1 * m)), abscissa<kilometre, int>(0 * km)));
+static_assert(comp(quantity_point_kind_cast<length<centimetre, int>>(abscissa<metre, int>(1 * m)), abscissa<centimetre, int>(100 * cm)));
+static_assert(comp(quantity_point_kind_cast<length<centimetre, int>>(abscissa<metre, double>(0.01 * m)), abscissa<centimetre, int>(1 * cm)));
+static_assert(comp(quantity_point_kind_cast<length<centimetre, int>>(abscissa<cgs::centimetre, int>(1 * cgs_cm)), abscissa<cgs::centimetre, int>(1 * cgs_cm)));
 static_assert(same(quantity_point_kind_cast<screen_si_cgs_width<metre, int>>(screen_si_width<metre, int>(1 * m)), screen_si_cgs_width<metre, int>(1 * m)));
 // clang-format on
 template<typename Int>
diff --git a/test/unit_test/static/quantity_test.cpp b/test/unit_test/static/quantity_test.cpp
index 9f9b87ae..f01f4a89 100644
--- a/test/unit_test/static/quantity_test.cpp
+++ b/test/unit_test/static/quantity_test.cpp
@@ -427,11 +427,11 @@ static_assert(invalid_binary_operations<metre>);
 static_assert(is_same_v<decltype(1_q_m + 1_q_m), length<metre, std::int64_t>>);
 static_assert(is_same_v<decltype(1_q_m - 1_q_m), length<metre, std::int64_t>>);
 static_assert(is_same_v<decltype(1_q_m * 1), length<metre, std::int64_t>>);
-static_assert(is_same_v<decltype(1_q_m * quantity{1}), length<metre, std::int64_t>>);
+static_assert(compare<decltype(1_q_m * quantity{1}), length<metre, std::int64_t>>);
 static_assert(is_same_v<decltype(1 * 1_q_m), length<metre, std::int64_t>>);
-static_assert(is_same_v<decltype(quantity{1} * 1_q_m), length<metre, std::int64_t>>);
+static_assert(compare<decltype(quantity{1} * 1_q_m), length<metre, std::int64_t>>);
 static_assert(is_same_v<decltype(1_q_m / 1), length<metre, std::int64_t>>);
-static_assert(is_same_v<decltype(1_q_m / quantity{1}), length<metre, std::int64_t>>);
+static_assert(compare<decltype(1_q_m / quantity{1}), length<metre, std::int64_t>>);
 static_assert(is_same_v<decltype(1_q_m % 1), length<metre, std::int64_t>>);
 static_assert(is_same_v<decltype(1_q_m % quantity{1}), length<metre, std::int64_t>>);
 static_assert(is_same_v<decltype(1_q_m % 1_q_m), length<metre, std::int64_t>>);
@@ -458,10 +458,10 @@ static_assert(is_same_v<decltype(1_q_m + 1._q_m), length<metre, long double>>);
 static_assert(is_same_v<decltype(1_q_m - 1._q_m), length<metre, long double>>);
 static_assert(is_same_v<decltype(1_q_m * 1.L), length<metre, long double>>);  // TODO should we address fundamental types implicit truncating conversions with concepts?
 static_assert(is_same_v<decltype(1 * 1._q_m), length<metre, long double>>);
-static_assert(is_same_v<decltype(1_q_m * quantity{1.L}), length<metre, long double>>);  // TODO should we address fundamental types implicit truncating conversions with concepts?
-static_assert(is_same_v<decltype(quantity{1} * 1._q_m), length<metre, long double>>);
+static_assert(compare<decltype(1_q_m * quantity{1.L}), length<metre, long double>>);  // TODO should we address fundamental types implicit truncating conversions with concepts?
+static_assert(compare<decltype(quantity{1} * 1._q_m), length<metre, long double>>);
 static_assert(is_same_v<decltype(1_q_m / 1.L), length<metre, long double>>);
-static_assert(is_same_v<decltype(1_q_m / quantity{1.L}), length<metre, long double>>);
+static_assert(compare<decltype(1_q_m / quantity{1.L}), length<metre, long double>>);
 static_assert(compare<decltype(1_q_m * dimensionless<percent, long double>(1)), length<centimetre, long double>>);
 static_assert(compare<decltype(dimensionless<percent, std::int64_t>(1) * 1._q_m), length<centimetre, long double>>);
 static_assert(compare<decltype(1_q_m * 1._q_m), area<square_metre, long double>>);
@@ -479,10 +479,10 @@ static_assert(is_same_v<decltype(1._q_m + 1_q_m), length<metre, long double>>);
 static_assert(is_same_v<decltype(1._q_m - 1_q_m), length<metre, long double>>);
 static_assert(is_same_v<decltype(1._q_m * 1), length<metre, long double>>);
 static_assert(is_same_v<decltype(1.L * 1_q_m), length<metre, long double>>);
-static_assert(is_same_v<decltype(1._q_m * quantity{1}), length<metre, long double>>);
-static_assert(is_same_v<decltype(quantity{1.L} * 1_q_m), length<metre, long double>>);
+static_assert(compare<decltype(1._q_m * quantity{1}), length<metre, long double>>);
+static_assert(compare<decltype(quantity{1.L} * 1_q_m), length<metre, long double>>);
 static_assert(is_same_v<decltype(1._q_m / 1), length<metre, long double>>);
-static_assert(is_same_v<decltype(1._q_m / quantity{1}), length<metre, long double>>);
+static_assert(compare<decltype(1._q_m / quantity{1}), length<metre, long double>>);
 static_assert(compare<decltype(1._q_m * dimensionless<percent, std::int64_t>(1)), length<centimetre, long double>>);
 static_assert(compare<decltype(dimensionless<percent, long double>(1) * 1_q_m), length<centimetre, long double>>);
 static_assert(compare<decltype(1._q_m / dimensionless<percent, std::int64_t>(1)), length<hectometre, long double>>);
@@ -493,25 +493,25 @@ static_assert(compare<decltype(quantity{1.L} / 1_q_s), frequency<hertz, long dou
 static_assert(compare<decltype(dimensionless<percent, long double>(1) / 1_q_s), frequency<scaled_unit<ratio(1, 100), hertz>, long double>>);
 
 // different units
-static_assert(is_same_v<decltype(1_q_m + 1_q_km), length<metre, std::int64_t>>);
-static_assert(is_same_v<decltype(1._q_m + 1_q_km), length<metre, long double>>);
-static_assert(is_same_v<decltype(1_q_m + 1._q_km), length<metre, long double>>);
-static_assert(is_same_v<decltype(1._q_m + 1._q_km), length<metre, long double>>);
+static_assert(compare<decltype(1_q_m + 1_q_km), length<metre, std::int64_t>>);
+static_assert(compare<decltype(1._q_m + 1_q_km), length<metre, long double>>);
+static_assert(compare<decltype(1_q_m + 1._q_km), length<metre, long double>>);
+static_assert(compare<decltype(1._q_m + 1._q_km), length<metre, long double>>);
 
-static_assert(is_same_v<decltype(1_q_km + 1_q_m), length<metre, std::int64_t>>);
-static_assert(is_same_v<decltype(1._q_km + 1_q_m), length<metre, long double>>);
-static_assert(is_same_v<decltype(1_q_km + 1._q_m), length<metre, long double>>);
-static_assert(is_same_v<decltype(1._q_km + 1._q_m), length<metre, long double>>);
+static_assert(compare<decltype(1_q_km + 1_q_m), length<metre, std::int64_t>>);
+static_assert(compare<decltype(1._q_km + 1_q_m), length<metre, long double>>);
+static_assert(compare<decltype(1_q_km + 1._q_m), length<metre, long double>>);
+static_assert(compare<decltype(1._q_km + 1._q_m), length<metre, long double>>);
 
-static_assert(is_same_v<decltype(1_q_m - 1_q_km), length<metre, std::int64_t>>);
-static_assert(is_same_v<decltype(1._q_m - 1_q_km), length<metre, long double>>);
-static_assert(is_same_v<decltype(1_q_m - 1._q_km), length<metre, long double>>);
-static_assert(is_same_v<decltype(1._q_m - 1._q_km), length<metre, long double>>);
+static_assert(compare<decltype(1_q_m - 1_q_km), length<metre, std::int64_t>>);
+static_assert(compare<decltype(1._q_m - 1_q_km), length<metre, long double>>);
+static_assert(compare<decltype(1_q_m - 1._q_km), length<metre, long double>>);
+static_assert(compare<decltype(1._q_m - 1._q_km), length<metre, long double>>);
 
-static_assert(is_same_v<decltype(1_q_km - 1_q_m), length<metre, std::int64_t>>);
-static_assert(is_same_v<decltype(1._q_km - 1_q_m), length<metre, long double>>);
-static_assert(is_same_v<decltype(1_q_km - 1._q_m), length<metre, long double>>);
-static_assert(is_same_v<decltype(1._q_km - 1._q_m), length<metre, long double>>);
+static_assert(compare<decltype(1_q_km - 1_q_m), length<metre, std::int64_t>>);
+static_assert(compare<decltype(1._q_km - 1_q_m), length<metre, long double>>);
+static_assert(compare<decltype(1_q_km - 1._q_m), length<metre, long double>>);
+static_assert(compare<decltype(1._q_km - 1._q_m), length<metre, long double>>);
 
 static_assert(is_same_v<decltype(1_q_m % 1_q_km), length<metre, std::int64_t>>);
 static_assert(is_same_v<decltype(1_q_km % 1_q_m), length<kilometre, std::int64_t>>);
@@ -820,8 +820,8 @@ static_assert(is_same_v<decltype(1_q_mm + 1_q_km), length<scaled_unit<ratio(1, 1
 
 #else
 
-static_assert(is_same_v<decltype(10_q_m / 5_q_s), speed<metre_per_second, std::int64_t>>);
-static_assert(is_same_v<decltype(1_q_mm + 1_q_km), length<millimetre, std::int64_t>>);
+static_assert(compare<decltype(10_q_m / 5_q_s), speed<metre_per_second, std::int64_t>>);
+static_assert(compare<decltype(1_q_mm + 1_q_km), length<millimetre, std::int64_t>>);
 
 #endif
 
@@ -835,17 +835,17 @@ constexpr auto quotient_remainder_theorem(auto q1, auto q2)
   return q;
 }
 
-static_assert(same(quotient_remainder_theorem(3'000 * m, 400 * m), 3'000 * m));
-static_assert(same(quotient_remainder_theorem(3 * km, 400 * m), 3 * km));
-static_assert(same(quotient_remainder_theorem(3 * km, 2 * m), 3 * km));
-static_assert(same(quotient_remainder_theorem(3 * km, 400'000 * mm), 3 * km));
-static_assert(same(quotient_remainder_theorem(3 * km, 2'000 * mm), 3 * km));
-static_assert(same(quotient_remainder_theorem(3 * km, 400 * mm), 3 * km));
-static_assert(same(quotient_remainder_theorem(3 * km, 2 * mm), 3 * km));
+static_assert(comp(quotient_remainder_theorem(3'000 * m, 400 * m), 3'000 * m));
+static_assert(comp(quotient_remainder_theorem(3 * km, 400 * m), 3 * km));
+static_assert(comp(quotient_remainder_theorem(3 * km, 2 * m), 3 * km));
+static_assert(comp(quotient_remainder_theorem(3 * km, 400'000 * mm), 3 * km));
+static_assert(comp(quotient_remainder_theorem(3 * km, 2'000 * mm), 3 * km));
+static_assert(comp(quotient_remainder_theorem(3 * km, 400 * mm), 3 * km));
+static_assert(comp(quotient_remainder_theorem(3 * km, 2 * mm), 3 * km));
 static_assert(same(quotient_remainder_theorem(3'000 * m, 400), 3'000 * m));
-static_assert(same(quotient_remainder_theorem(3'000 * m, quantity(400)), 3'000 * m));
-static_assert(same(quotient_remainder_theorem(3 * km, quantity(400)), 3 * km));
-static_assert(same(quotient_remainder_theorem(3 * km, quantity(2)), 3 * km));
-static_assert(same(quotient_remainder_theorem(3 * km, dimensionless<scaled_unit<ratio(1, 1000), one>, int>(400)), 3 * km));
+static_assert(comp(quotient_remainder_theorem(3'000 * m, quantity(400)), 3'000 * m));
+static_assert(comp(quotient_remainder_theorem(3 * km, quantity(400)), 3 * km));
+static_assert(comp(quotient_remainder_theorem(3 * km, quantity(2)), 3 * km));
+static_assert(comp(quotient_remainder_theorem(3 * km, dimensionless<scaled_unit<ratio(1, 1000), one>, int>(400)), 3 * km));
 
 }  // namespace
diff --git a/test/unit_test/static/references_test.cpp b/test/unit_test/static/references_test.cpp
index 670f0975..f3072acf 100644
--- a/test/unit_test/static/references_test.cpp
+++ b/test/unit_test/static/references_test.cpp
@@ -20,6 +20,7 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
+#include "test_tools.h"
 #include <units/bits/external/hacks.h>
 #include <units/bits/external/type_traits.h>
 #include <units/isq/si/area.h>
@@ -70,8 +71,8 @@ static_assert([] {
   const auto duration{2};
   return length * km / (duration * h);
 }() == 60_q_km_per_h);
-static_assert(is_same_v<decltype(std::int64_t{120} * km / (2 * h)), decltype(60_q_km_per_h)>);
-static_assert(is_same_v<decltype(120.L * km / (2 * h)), decltype(60._q_km_per_h)>);
+static_assert(compare<decltype(std::int64_t{120} * km / (2 * h)), decltype(60_q_km_per_h)>);
+static_assert(compare<decltype(120.L * km / (2 * h)), decltype(60._q_km_per_h)>);
 
 static_assert(1. / 4 * m2 == 1._q_m2 / 4);
 
diff --git a/test/unit_test/static/test_tools.h b/test/unit_test/static/test_tools.h
index 70ef41a1..4116ed7c 100644
--- a/test/unit_test/static/test_tools.h
+++ b/test/unit_test/static/test_tools.h
@@ -123,16 +123,9 @@ constexpr bool ctad_constructible_from(Vs...)
   return ctad_constructible_from_<T, void, Us..., Vs...>;
 }
 
-#if UNITS_DOWNCAST_MODE
 constexpr auto same = []<std::equality_comparable T>(T l, T r) { return l == r; };
-#else
-constexpr auto same = []<typename T, typename U>(T l, U r)
-  requires requires { l == r; }
-// requires std::equality_comparable_with<T, U>  // TODO: Fix #205
-{
-  return l == r;
-};
-#endif
+constexpr auto comp = // TODO: Fix #205 to use `std::equality_comparable_with<T> U`.
+  []<typename T, typename U>(T l, U r) requires compare<T, U> { return l == r; };
 
 template<auto F>
   requires requires { F(); }

From 061b7652d36b58abafc623644aab821268424763 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 15 Apr 2022 16:56:48 +0200
Subject: [PATCH 02/68] style: conanfile.py reformatted

---
 conanfile.py | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/conanfile.py b/conanfile.py
index 924700cb..0d7c2dd3 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -28,11 +28,24 @@ import os, re
 
 required_conan_version = ">=1.44.0"
 
+
 class MPUnitsConan(ConanFile):
     name = "mp-units"
     homepage = "https://github.com/mpusz/units"
     description = "Physical Units library for C++"
-    topics = ("units", "dimensions", "quantities", "dimensional-analysis", "physical-quantities", "physical-units", "system-of-units", "cpp23", "cpp20", "library", "quantity-manipulation")
+    topics = (
+        "units",
+        "dimensions",
+        "quantities",
+        "dimensional-analysis",
+        "physical-quantities",
+        "physical-units",
+        "system-of-units",
+        "cpp23",
+        "cpp20",
+        "library",
+        "quantity-manipulation",
+    )
     license = "MIT"
     url = "https://github.com/mpusz/units"
     settings = "os", "compiler", "build_type", "arch"
@@ -48,7 +61,7 @@ class MPUnitsConan(ConanFile):
         "build_docs": True
     }
     exports = ["LICENSE.md"]
-    exports_sources = ["docs/*", "src/*", "test/*", "cmake/*", "example/*","CMakeLists.txt"]
+    exports_sources = ["docs/*", "src/*", "test/*", "cmake/*", "example/*", "CMakeLists.txt"]
     generators = "cmake_paths"
 
     @property
@@ -68,12 +81,12 @@ class MPUnitsConan(ConanFile):
     def _use_range_v3(self):
         compiler = self.settings.compiler
         version = Version(self.settings.compiler.version)
-        return ("clang" in compiler and compiler.libcxx == "libc++" and version < 14)
+        return "clang" in compiler and compiler.libcxx == "libc++" and version < 14
 
     @property
     def _msvc_version(self):
         compiler = self.settings.compiler
-        if (compiler.update):
+        if compiler.update:
             return int(f"{compiler.version}{compiler.update}")
         else:
             return int(f"{compiler.version}0")

From 9abd63c2d56504ebd4af00e3ea41e8baf17b19d8 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 15 Apr 2022 16:57:38 +0200
Subject: [PATCH 03/68] fix: `validate()` replaced with `configure()` to raise
 errors during `conan install` in Conan 1.X

---
 conanfile.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/conanfile.py b/conanfile.py
index 0d7c2dd3..2cfa1810 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -110,7 +110,8 @@ class MPUnitsConan(ConanFile):
             if self.options.build_docs:
                 self.tool_requires("doxygen/1.9.2")
 
-    def validate(self):
+    # TODO Replace with `valdate()` for Conan 2.0 (https://github.com/conan-io/conan/issues/10723)
+    def configure(self):
         compiler = self.settings.compiler
         version = Version(self.settings.compiler.version)
         if compiler == "gcc":

From 05fecca12cc48e2dc2b53d06592625823839ecd8 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 15 Apr 2022 17:00:02 +0200
Subject: [PATCH 04/68] refactor: `self.copy` replaced by the explicit tool
 `copy` (for Conan 2.0)

---
 conanfile.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/conanfile.py b/conanfile.py
index 2cfa1810..01b90f62 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -23,6 +23,7 @@
 from conans import ConanFile, tools
 from conans.tools import Version, check_min_cppstd
 from conan.tools.cmake import CMakeToolchain, CMakeDeps, CMake
+from conan.tools.files import copy
 from conans.errors import ConanInvalidConfiguration
 import os, re
 
@@ -160,7 +161,7 @@ class MPUnitsConan(ConanFile):
         self.info.header_only()
 
     def package(self):
-        self.copy("LICENSE.md", dst="licenses")
+        copy(self, "LICENSE.md", self.source_folder, os.path.join(self.package_folder, "licenses"))
         cmake = CMake(self)
         cmake.install()
         tools.rmdir(os.path.join(self.package_folder, "lib", "cmake"))

From 10a1c06dfa1d36c4a300436eaafd8c3df9cbf5b5 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 15 Apr 2022 17:01:47 +0200
Subject: [PATCH 05/68] fix: `includedirs` added for components as there will
 be no defaults in Conan 2.0

---
 conanfile.py | 44 +++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 43 insertions(+), 1 deletion(-)

diff --git a/conanfile.py b/conanfile.py
index 01b90f62..98add025 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -171,6 +171,7 @@ class MPUnitsConan(ConanFile):
 
         # core
         self.cpp_info.components["core"].requires = ["gsl-lite::gsl-lite"]
+        self.cpp_info.components["core"].includedirs = ["include"]
         if compiler == "Visual Studio":
             self.cpp_info.components["core"].cxxflags = ["/utf-8"]
         if self._use_range_v3:
@@ -178,19 +179,60 @@ class MPUnitsConan(ConanFile):
 
         # rest
         self.cpp_info.components["core-io"].requires = ["core"]
+        self.cpp_info.components["core-io"].includedirs = ["include"]
+
         self.cpp_info.components["core-fmt"].requires = ["core"]
+        self.cpp_info.components["core-fmt"].includedirs = ["include"]
         if self._use_libfmt:
             self.cpp_info.components["core-fmt"].requires.append("fmt::fmt")
+
         self.cpp_info.components["isq"].requires = ["core"]
+        self.cpp_info.components["isq"].includedirs = ["include"]
+
         self.cpp_info.components["isq-natural"].requires = ["isq"]
+        self.cpp_info.components["isq-natural"].includedirs = ["include"]
+
         self.cpp_info.components["si"].requires = ["isq"]
+        self.cpp_info.components["si"].includedirs = ["include"]
+
         self.cpp_info.components["si-cgs"].requires = ["si"]
+        self.cpp_info.components["si-cgs"].includedirs = ["include"]
+
         self.cpp_info.components["si-fps"].requires = ["si"]
+        self.cpp_info.components["si-fps"].includedirs = ["include"]
+
         self.cpp_info.components["si-hep"].requires = ["si"]
+        self.cpp_info.components["si-hep"].includedirs = ["include"]
+
         self.cpp_info.components["si-iau"].requires = ["si"]
+        self.cpp_info.components["si-iau"].includedirs = ["include"]
+
         self.cpp_info.components["si-imperial"].requires = ["si"]
+        self.cpp_info.components["si-imperial"].includedirs = ["include"]
+
         self.cpp_info.components["si-international"].requires = ["si"]
+        self.cpp_info.components["si-international"].includedirs = ["include"]
+
         self.cpp_info.components["si-typographic"].requires = ["si"]
+        self.cpp_info.components["si-typographic"].includedirs = ["include"]
+
         self.cpp_info.components["si-uscs"].requires = ["si"]
+        self.cpp_info.components["si-uscs"].includedirs = ["include"]
+
         self.cpp_info.components["isq-iec80000"].requires = ["si"]
-        self.cpp_info.components["systems"].requires = ["isq", "isq-natural", "si", "si-cgs", "si-fps", "si-hep", "si-iau", "si-imperial", "si-international", "si-typographic", "si-uscs", "isq-iec80000"]
+        self.cpp_info.components["isq-iec80000"].includedirs = ["include"]
+
+        self.cpp_info.components["systems"].requires = [
+            "isq",
+            "isq-natural",
+            "si",
+            "si-cgs",
+            "si-fps",
+            "si-hep",
+            "si-iau",
+            "si-imperial",
+            "si-international",
+            "si-typographic",
+            "si-uscs",
+            "isq-iec80000",
+        ]

From ac8e32fcdae5685277f0e3d0e574b7c0188f6cf7 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 15 Apr 2022 17:07:55 +0200
Subject: [PATCH 06/68] feat: Conan 2.0 requires the explicit declaration of
 the requirement being tested

---
 test_package/conanfile.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/test_package/conanfile.py b/test_package/conanfile.py
index babc60b1..9a98ad73 100644
--- a/test_package/conanfile.py
+++ b/test_package/conanfile.py
@@ -23,9 +23,14 @@
 from conans import ConanFile, tools
 from conan.tools.cmake import CMake
 
+
 class TestPackageConan(ConanFile):
     settings = "os", "compiler", "build_type", "arch"
     generators = "CMakeToolchain", "CMakeDeps"
+    test_type = "explicit"  # TODO Remove for Conan 2.0
+
+    def requirements(self):
+        self.requires(self.tested_reference_str)
 
     def build(self):
         cmake = CMake(self)

From 291314fbb743b2025475732480efb8251d534a95 Mon Sep 17 00:00:00 2001
From: Aleksei Latyshev <alex_700_95@mail.ru>
Date: Sun, 17 Apr 2022 23:49:19 +0300
Subject: [PATCH 07/68] docs: fix typo in units.rst

---
 docs/framework/units.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/framework/units.rst b/docs/framework/units.rst
index 86dd0e1b..9e00b7ee 100644
--- a/docs/framework/units.rst
+++ b/docs/framework/units.rst
@@ -193,7 +193,7 @@ namely second. Those can be defined easily in the library using
 
     struct minute : named_scaled_unit<minute, "min", no_prefix, ratio(60), second> {};
     struct hour : named_scaled_unit<hour, "h", no_prefix, ratio(60), minute> {};
-    struct day : named_scaled_unit<hour, "d", no_prefix, ratio(24), hour> {};
+    struct day : named_scaled_unit<day, "d", no_prefix, ratio(24), hour> {};
 
 where `no_prefix` is a special tag type describing that the library should
 not allow to define a new prefixed unit that would use this unit as a

From a0c625256719ec04b1be948bccb57c776774c7ef Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Tue, 19 Apr 2022 18:45:13 +0200
Subject: [PATCH 08/68] refactor: `mi(naut)` renamed to `nmi`

Relates to #357
---
 src/systems/si-fps/include/units/isq/si/fps/length.h            | 2 +-
 .../include/units/isq/si/international/length.h                 | 2 +-
 test/unit_test/runtime/fmt_units_test.cpp                       | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/systems/si-fps/include/units/isq/si/fps/length.h b/src/systems/si-fps/include/units/isq/si/fps/length.h
index c037afe1..a4307180 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/length.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/length.h
@@ -52,7 +52,7 @@ struct kiloyard : prefixed_unit<kiloyard, si::kilo, yard> {};
 
 struct mile : named_scaled_unit<mile, "mile", no_prefix, ratio(5'280), foot> {};
 
-struct nautical_mile : named_scaled_unit<nautical_mile, "mi(naut)", no_prefix, ratio(2'000), yard> {};
+struct nautical_mile : named_scaled_unit<nautical_mile, "nmi", no_prefix, ratio(2'000), yard> {};
 
 struct dim_length : isq::dim_length<foot> {};
 
diff --git a/src/systems/si-international/include/units/isq/si/international/length.h b/src/systems/si-international/include/units/isq/si/international/length.h
index 38b7eac3..e37944a0 100644
--- a/src/systems/si-international/include/units/isq/si/international/length.h
+++ b/src/systems/si-international/include/units/isq/si/international/length.h
@@ -56,7 +56,7 @@ struct mile : named_scaled_unit<mile, "mi", no_prefix, ratio(25'146, 15'625), si
 
 // si::international nautical mile
 // https://en.wikipedia.org/wiki/Nautical_mile
-struct nautical_mile : named_scaled_unit<nautical_mile, "mi(naut)", no_prefix, ratio(1852), si::metre> {};
+struct nautical_mile : named_scaled_unit<nautical_mile, "nmi", no_prefix, ratio(1852), si::metre> {};
 
 // thou
 // https://en.wikipedia.org/wiki/Thousandth_of_an_inch
diff --git a/test/unit_test/runtime/fmt_units_test.cpp b/test/unit_test/runtime/fmt_units_test.cpp
index c94c3734..8414e5a0 100644
--- a/test/unit_test/runtime/fmt_units_test.cpp
+++ b/test/unit_test/runtime/fmt_units_test.cpp
@@ -65,7 +65,7 @@ TEST_CASE("std::format on synthesized unit symbols", "[text][fmt]")
     CHECK(STD_FMT::format("{}", 1_q_fathom_us) == "1 fathom(us)");
     CHECK(STD_FMT::format("{}", 1_q_mi) == "1 mi");
     CHECK(STD_FMT::format("{}", 1_q_mi_us) == "1 mi(us)");
-    CHECK(STD_FMT::format("{}", 1_q_naut_mi) == "1 mi(naut)");
+    CHECK(STD_FMT::format("{}", 1_q_naut_mi) == "1 nmi");
     CHECK(STD_FMT::format("{}", 1_q_ch) == "1 ch");
     CHECK(STD_FMT::format("{}", 1_q_rd) == "1 rd");
     CHECK(STD_FMT::format("{}", 1_q_thou) == "1 thou");

From 999ff52d701dda9c8d118e688612e5026209e552 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Tue, 19 Apr 2022 18:48:46 +0200
Subject: [PATCH 09/68] refactor: `knot` unit helper renamed to `kn` in FPS

Relates to #357
---
 example/aliases/foot_pound_second.cpp               | 6 +++---
 example/literals/foot_pound_second.cpp              | 4 ++--
 example/references/foot_pound_second.cpp            | 4 ++--
 src/systems/si-fps/include/units/isq/si/fps/speed.h | 8 ++++----
 4 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/example/aliases/foot_pound_second.cpp b/example/aliases/foot_pound_second.cpp
index 588e328d..12b1082d 100644
--- a/example/aliases/foot_pound_second.cpp
+++ b/example/aliases/foot_pound_second.cpp
@@ -68,7 +68,7 @@ void print_details(std::string_view description, const Ship& ship)
             << STD_FMT::format("{:20} : {}\n", "beam", fmt_line<si::fps::length::yd<>, si::length::m<>>(ship.beam))
             << STD_FMT::format("{:20} : {}\n", "mass", fmt_line<si::fps::mass::lton<>, si::mass::t<>>(ship.mass))
             << STD_FMT::format("{:20} : {}\n", "speed",
-                               fmt_line<si::fps::speed::knot<>, si::speed::km_per_h<>>(ship.speed))
+                               fmt_line<si::fps::speed::kn<>, si::speed::km_per_h<>>(ship.speed))
             << STD_FMT::format("{:20} : {}\n", "power", fmt_line<si::fps::power::hp<>, si::power::kW<>>(ship.power))
             << STD_FMT::format("{:20} : {}\n", "main guns",
                                fmt_line<si::fps::length::in<>, si::length::mm<>>(ship.mainGuns))
@@ -101,7 +101,7 @@ int main()
   auto iowa = Ship{.length{ft<>(860.)},
                    .draft{ft<>(37.) + in<>(2.)},
                    .beam{ft<>(108.) + in<>(2.)},
-                   .speed{knot<>(33)},
+                   .speed{kn<>(33)},
                    .mass{lton<>(57'540)},
                    .mainGuns{in<>(16)},
                    .shellMass{lb<>(2700)},
@@ -112,7 +112,7 @@ int main()
   auto kgv = Ship{.length{ft<>(745.1)},
                   .draft{ft<>(33.) + in<>(7.5)},
                   .beam{ft<>(103.2) + in<>(2.5)},
-                  .speed{knot<>(28.3)},
+                  .speed{kn<>(28.3)},
                   .mass{lton<>(42'245)},
                   .mainGuns{in<>(14)},
                   .shellMass{lb<>(1'590)},
diff --git a/example/literals/foot_pound_second.cpp b/example/literals/foot_pound_second.cpp
index 69df4f51..67d1d296 100644
--- a/example/literals/foot_pound_second.cpp
+++ b/example/literals/foot_pound_second.cpp
@@ -108,7 +108,7 @@ int main()
   auto iowa = Ship{.length{860._q_ft},
                    .draft{37._q_ft + 2._q_in},
                    .beam{108._q_ft + 2._q_in},
-                   .speed{33_q_knot},
+                   .speed{33_q_kn},
                    .mass{57'540_q_lton},
                    .mainGuns{16_q_in},
                    .shellMass{2700_q_lb},
@@ -119,7 +119,7 @@ int main()
   auto kgv = Ship{.length{745.1_q_ft},
                   .draft{33._q_ft + 7.5_q_in},
                   .beam{103.2_q_ft + 2.5_q_in},
-                  .speed{28.3_q_knot},
+                  .speed{28.3_q_kn},
                   .mass{42'245_q_lton},
                   .mainGuns{14_q_in},
                   .shellMass{1'590_q_lb},
diff --git a/example/references/foot_pound_second.cpp b/example/references/foot_pound_second.cpp
index f947ed4c..ca1f5447 100644
--- a/example/references/foot_pound_second.cpp
+++ b/example/references/foot_pound_second.cpp
@@ -112,7 +112,7 @@ int main()
   auto iowa = Ship{.length{860. * ft},
                    .draft{37. * ft + 2. * in},
                    .beam{108. * ft + 2. * in},
-                   .speed{33 * knot},
+                   .speed{33 * kn},
                    .mass{57'540 * lton},
                    .mainGuns{16 * in},
                    .shellMass{2700 * lb},
@@ -123,7 +123,7 @@ int main()
   auto kgv = Ship{.length{745.1 * ft},
                   .draft{33. * ft + 7.5 * in},
                   .beam{103.2 * ft + 2.5 * in},
-                  .speed{28.3 * knot},
+                  .speed{28.3 * kn},
                   .mass{42'245 * lton},
                   .mainGuns{14 * in},
                   .shellMass{1'590 * lb},
diff --git a/src/systems/si-fps/include/units/isq/si/fps/speed.h b/src/systems/si-fps/include/units/isq/si/fps/speed.h
index 04302b86..cc78443f 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/speed.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/speed.h
@@ -66,12 +66,12 @@ constexpr auto operator"" _q_mph(unsigned long long l)
 constexpr auto operator"" _q_mph(long double l) { return speed<mile_per_hour, long double>(l); }
 
 // kn
-constexpr auto operator"" _q_knot(unsigned long long l)
+constexpr auto operator"" _q_kn(unsigned long long l)
 {
   gsl_ExpectsAudit(std::in_range<std::int64_t>(l));
   return speed<knot, std::int64_t>(static_cast<std::int64_t>(l));
 }
-constexpr auto operator"" _q_knot(long double l) { return speed<knot, long double>(l); }
+constexpr auto operator"" _q_kn(long double l) { return speed<knot, long double>(l); }
 
 }  // namespace literals
 
@@ -82,7 +82,7 @@ constexpr auto operator"" _q_knot(long double l) { return speed<knot, long doubl
 namespace speed_references {
 
 inline constexpr auto mph = reference<dim_speed, mile_per_hour>{};
-inline constexpr auto knot = reference<dim_speed, fps::knot>{};
+inline constexpr auto kn = reference<dim_speed, fps::knot>{};
 
 }  // namespace speed_references
 
@@ -105,7 +105,7 @@ using ft_per_s = units::isq::si::fps::speed<units::isq::si::fps::foot_per_second
 template<Representation Rep = double>
 using mph = units::isq::si::fps::speed<units::isq::si::fps::mile_per_hour, Rep>;
 template<Representation Rep = double>
-using knot = units::isq::si::fps::speed<units::isq::si::fps::knot, Rep>;
+using kn = units::isq::si::fps::speed<units::isq::si::fps::knot, Rep>;
 
 }  // namespace units::aliases::isq::si::fps::inline speed
 

From e660278fa893132cc0782e3fccc369896c00dabd Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Tue, 19 Apr 2022 18:49:48 +0200
Subject: [PATCH 10/68] feat: `nautical_mile_per_hour` and `knot` added to
 `si::international` system

Relates to #357
---
 .../units/isq/si/international/speed.h        | 41 +++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/src/systems/si-international/include/units/isq/si/international/speed.h b/src/systems/si-international/include/units/isq/si/international/speed.h
index 3ce51418..df074b84 100644
--- a/src/systems/si-international/include/units/isq/si/international/speed.h
+++ b/src/systems/si-international/include/units/isq/si/international/speed.h
@@ -35,6 +35,9 @@
 namespace units::isq::si::international {
 
 struct mile_per_hour : derived_unit<mile_per_hour, si::dim_speed, si::international::mile, si::hour> {};
+struct nautical_mile_per_hour :
+    derived_unit<nautical_mile_per_hour, si::dim_speed, si::international::nautical_mile, si::hour> {};
+struct knot : alias_unit<nautical_mile_per_hour, "knot", no_prefix> {};
 
 #ifndef UNITS_NO_LITERALS
 
@@ -48,10 +51,42 @@ constexpr auto operator"" _q_mi_per_h(unsigned long long l)
 }
 constexpr auto operator"" _q_mi_per_h(long double l) { return si::speed<mile_per_hour, long double>(l); }
 
+// nmi/h
+constexpr auto operator"" _q_nmi_per_h(unsigned long long l)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(l));
+  return si::speed<nautical_mile_per_hour, std::int64_t>(static_cast<std::int64_t>(l));
+}
+constexpr auto operator"" _q_nmi_per_h(long double l) { return si::speed<nautical_mile_per_hour, long double>(l); }
+
+// kn
+constexpr auto operator"" _q_kn(unsigned long long l)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(l));
+  return si::speed<knot, std::int64_t>(static_cast<std::int64_t>(l));
+}
+constexpr auto operator"" _q_kn(long double l) { return si::speed<knot, long double>(l); }
+
 }  // namespace literals
 
 #endif  // UNITS_NO_LITERALS
 
+#ifndef UNITS_NO_REFERENCES
+
+namespace speed_references {
+
+inline constexpr auto kn = reference<si::dim_speed, knot>{};
+
+}  // namespace speed_references
+
+namespace references {
+
+using namespace speed_references;
+
+}  // namespace references
+
+#endif  // UNITS_NO_REFERENCES
+
 }  // namespace units::isq::si::international
 
 #ifndef UNITS_NO_ALIASES
@@ -61,6 +96,12 @@ namespace units::aliases::isq::si::international::inline speed {
 template<Representation Rep = double>
 using mi_per_h = units::isq::si::speed<units::isq::si::international::mile_per_hour, Rep>;
 
+template<Representation Rep = double>
+using nmi_per_h = units::isq::si::speed<units::isq::si::international::nautical_mile_per_hour, Rep>;
+
+template<Representation Rep = double>
+using kn = units::isq::si::speed<units::isq::si::international::knot, Rep>;
+
 }  // namespace units::aliases::isq::si::international::inline speed
 
 #endif  // UNITS_NO_ALIASES

From e525c0c8928fa235cad8ae2b1a84c3270d40096c Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Tue, 19 Apr 2022 18:57:06 +0200
Subject: [PATCH 11/68] refactor: `knot` text symbol changed from `"knot"` to
 `"kn`"

Relates to #357
---
 src/systems/si-fps/include/units/isq/si/fps/speed.h             | 2 +-
 .../si-international/include/units/isq/si/international/speed.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/systems/si-fps/include/units/isq/si/fps/speed.h b/src/systems/si-fps/include/units/isq/si/fps/speed.h
index cc78443f..816aff3a 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/speed.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/speed.h
@@ -43,7 +43,7 @@ using speed = quantity<dim_speed, U, Rep>;
 
 struct mile_per_hour : derived_unit<mile_per_hour, dim_speed, mile, hour> {};
 struct nautical_mile_per_hour : derived_unit<nautical_mile_per_hour, dim_speed, nautical_mile, hour> {};
-struct knot : alias_unit<nautical_mile_per_hour, "knot", no_prefix> {};
+struct knot : alias_unit<nautical_mile_per_hour, "kn", no_prefix> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si-international/include/units/isq/si/international/speed.h b/src/systems/si-international/include/units/isq/si/international/speed.h
index df074b84..1f81a592 100644
--- a/src/systems/si-international/include/units/isq/si/international/speed.h
+++ b/src/systems/si-international/include/units/isq/si/international/speed.h
@@ -37,7 +37,7 @@ namespace units::isq::si::international {
 struct mile_per_hour : derived_unit<mile_per_hour, si::dim_speed, si::international::mile, si::hour> {};
 struct nautical_mile_per_hour :
     derived_unit<nautical_mile_per_hour, si::dim_speed, si::international::nautical_mile, si::hour> {};
-struct knot : alias_unit<nautical_mile_per_hour, "knot", no_prefix> {};
+struct knot : alias_unit<nautical_mile_per_hour, "kn", no_prefix> {};
 
 #ifndef UNITS_NO_LITERALS
 

From 11521a5a96358188965ea25673051480910f8625 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 21 Apr 2022 21:23:45 +0200
Subject: [PATCH 12/68] feat(example): `validated_type`  and
 `ranged_representation` example types added

---
 example/CMakeLists.txt                  |  3 +
 example/include/ranged_representation.h | 52 ++++++++++++++++
 example/include/validated_type.h        | 81 +++++++++++++++++++++++++
 3 files changed, 136 insertions(+)
 create mode 100644 example/include/ranged_representation.h
 create mode 100644 example/include/validated_type.h

diff --git a/example/CMakeLists.txt b/example/CMakeLists.txt
index 0e7a71b0..76117aa4 100644
--- a/example/CMakeLists.txt
+++ b/example/CMakeLists.txt
@@ -22,6 +22,9 @@
 
 cmake_minimum_required(VERSION 3.2)
 
+add_library(example_utils INTERFACE)
+target_include_directories(example_utils INTERFACE include)
+
 #
 # add_example(target <depependencies>...)
 #
diff --git a/example/include/ranged_representation.h b/example/include/ranged_representation.h
new file mode 100644
index 00000000..8d5ec234
--- /dev/null
+++ b/example/include/ranged_representation.h
@@ -0,0 +1,52 @@
+// The MIT License (MIT)
+//
+// Copyright (c) 2018 Mateusz Pusz
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+#pragma once
+
+#include "validated_type.h"
+#include <algorithm>
+#include <type_traits>
+
+template<auto Min, auto Max>
+inline constexpr auto is_in_range = [](const auto& v) { return std::clamp(v, Min, Max) == v; };
+
+template<typename T, T Min, T Max>
+class ranged_representation : public validated_type<T, decltype(is_in_range<Min, Max>)> {
+public:
+  using base = validated_type<T, decltype(is_in_range<Min, Max>)>;
+  using base::validated_type;
+  constexpr ranged_representation() : base(T{}) {}
+
+  [[nodiscard]] constexpr ranged_representation operator-() const { return ranged_representation(-this->value()); }
+};
+
+template<typename T, T Min, T Max>
+struct std::common_type<std::intmax_t, ranged_representation<T, Min, Max>> :
+    std::type_identity<
+      ranged_representation<std::common_type_t<std::intmax_t, T>, std::common_type_t<std::intmax_t, T>{Min},
+                            std::common_type_t<std::intmax_t, T>{Max}>> {};
+
+template<typename T, T Min, T Max>
+struct std::common_type<ranged_representation<T, Min, Max>, std::intmax_t> :
+    std::type_identity<
+      ranged_representation<std::common_type_t<T, std::intmax_t>, std::common_type_t<T, std::intmax_t>{Min},
+                            std::common_type_t<T, std::intmax_t>{Max}>> {};
diff --git a/example/include/validated_type.h b/example/include/validated_type.h
new file mode 100644
index 00000000..bf44bbbc
--- /dev/null
+++ b/example/include/validated_type.h
@@ -0,0 +1,81 @@
+// The MIT License (MIT)
+//
+// Copyright (c) 2018 Mateusz Pusz
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+#pragma once
+
+#include <gsl/gsl-lite.hpp>
+#include <units/bits/external/hacks.h>
+#include <utility>
+
+inline constexpr struct validated_tag {
+} validated;
+
+template<std::movable T, std::predicate<T> Validator>
+class validated_type {
+  T value_;
+public:
+  using value_type = T;
+
+  static constexpr bool validate(const T& value) { return Validator()(value); }
+
+  constexpr explicit validated_type(const T& value) noexcept(std::is_nothrow_copy_constructible_v<T>)
+    requires std::copyable<T>
+  : value_(value)
+  {
+    gsl_Expects(validate(value_));
+  }
+
+  constexpr explicit validated_type(T&& value) noexcept(std::is_nothrow_move_constructible_v<T>) :
+      value_(std::move(value))
+  {
+    gsl_Expects(validate(value_));
+  }
+
+  constexpr validated_type(const T& value, validated_tag) noexcept(std::is_nothrow_copy_constructible_v<T>)
+    requires std::copyable<T>
+  : value_(value)
+  {
+  }
+
+  constexpr validated_type(T&& value, validated_tag) noexcept(std::is_nothrow_move_constructible_v<T>) :
+      value_(std::move(value))
+  {
+  }
+
+  constexpr explicit(false) operator T() const noexcept(std::is_nothrow_copy_constructible_v<T>)
+    requires std::copyable<T>
+  {
+    return value_;
+  }
+
+  constexpr T& value() & noexcept = delete;
+  constexpr const T& value() const& noexcept { return value_; }
+  constexpr T&& value() && noexcept { return std::move(value_); }
+  constexpr const T&& value() const&& noexcept { return std::move(value_); }
+
+  bool operator==(const validated_type&) const
+    requires std::equality_comparable<T>
+  = default;
+  auto operator<=>(const validated_type&) const
+    requires std::three_way_comparable<T>
+  = default;
+};

From bded48987d075b94a58b50c126843a9e6cc853e1 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 21 Apr 2022 21:25:54 +0200
Subject: [PATCH 13/68] refactor(example): `glide_computer` now use
 dimensionless quantities with `ranged_representation` as `rep`

---
 example/glide_computer/CMakeLists.txt         |   4 +-
 example/glide_computer/geographic.cpp         |  64 --------
 example/glide_computer/include/geographic.h   | 153 +++++++++++-------
 .../glide_computer/include/glide_computer.h   |   2 +-
 4 files changed, 99 insertions(+), 124 deletions(-)
 delete mode 100644 example/glide_computer/geographic.cpp

diff --git a/example/glide_computer/CMakeLists.txt b/example/glide_computer/CMakeLists.txt
index d98b3636..7c19f4db 100644
--- a/example/glide_computer/CMakeLists.txt
+++ b/example/glide_computer/CMakeLists.txt
@@ -22,6 +22,6 @@
 
 cmake_minimum_required(VERSION 3.2)
 
-add_library(glide_computer STATIC geographic.cpp include/geographic.h glide_computer.cpp include/glide_computer.h)
-target_link_libraries(glide_computer PRIVATE mp-units::core-fmt PUBLIC mp-units::si)
+add_library(glide_computer STATIC include/geographic.h glide_computer.cpp include/glide_computer.h)
+target_link_libraries(glide_computer PRIVATE mp-units::core-fmt PUBLIC mp-units::si example_utils)
 target_include_directories(glide_computer PUBLIC include)
diff --git a/example/glide_computer/geographic.cpp b/example/glide_computer/geographic.cpp
deleted file mode 100644
index 4150c792..00000000
--- a/example/glide_computer/geographic.cpp
+++ /dev/null
@@ -1,64 +0,0 @@
-// The MIT License (MIT)
-//
-// Copyright (c) 2018 Mateusz Pusz
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in all
-// copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-// SOFTWARE.
-
-#include "geographic.h"
-#include <cmath>
-#include <numbers>
-#include <type_traits>
-
-namespace {
-
-using namespace units::isq::si;
-inline constexpr length<kilometre> earth_radius(6371);
-
-}  // namespace
-
-namespace geographic {
-
-distance spherical_distance(position from, position to)
-{
-  using rep = std::common_type_t<latitude::value_type, longitude::value_type>;
-  constexpr auto p = std::numbers::pi_v<rep> / 180;
-  const auto lat1 = from.lat.value() * p;
-  const auto lon1 = from.lon.value() * p;
-  const auto lat2 = to.lat.value() * p;
-  const auto lon2 = to.lon.value() * p;
-
-  using std::sin, std::cos, std::asin, std::sqrt;
-
-  // https://en.wikipedia.org/wiki/Great-circle_distance#Formulae
-  if constexpr (sizeof(rep) >= 8) {
-    // spherical law of cosines
-    const auto central_angle = acos(sin(lat1) * sin(lat2) + cos(lat1) * cos(lat2) * cos(lon2 - lon1));
-    // const auto central_angle = 2 * asin(sqrt(0.5 - cos(lat2 - lat1) / 2 + cos(lat1) * cos(lat2) * (1 - cos(lon2 -
-    // lon1)) / 2));
-    return distance(earth_radius * central_angle);
-  } else {
-    // the haversine formula
-    const auto sin_lat = sin((lat2 - lat1) / 2);
-    const auto sin_lon = sin((lon2 - lon1) / 2);
-    const auto central_angle = 2 * asin(sqrt(sin_lat * sin_lat + cos(lat1) * cos(lat2) * sin_lon * sin_lon));
-    return distance(earth_radius * central_angle);
-  }
-}
-
-}  // namespace geographic
diff --git a/example/glide_computer/include/geographic.h b/example/glide_computer/include/geographic.h
index 44290080..e8a56714 100644
--- a/example/glide_computer/include/geographic.h
+++ b/example/glide_computer/include/geographic.h
@@ -22,7 +22,9 @@
 
 #pragma once
 
+#include "ranged_representation.h"
 #include <units/bits/fmt_hacks.h>
+#include <units/generic/dimensionless.h>
 #include <units/isq/si/length.h>
 #include <units/quantity_kind.h>
 #include <limits>
@@ -34,88 +36,95 @@
 
 namespace geographic {
 
-template<typename Derived, typename Rep>
-struct coordinate {
-  using value_type = Rep;
-  constexpr explicit coordinate(value_type v) : value_(v) {}
-  constexpr value_type value() const { return value_; }
-  auto operator<=>(const coordinate&) const = default;
-private:
-  value_type value_;
-};
+// TODO Change to `angle` dimension in degree unit when the work on magnitudes is done
+template<typename T = double>
+using latitude = units::dimensionless<units::one, ranged_representation<T, T(-90), T(90)>>;
 
-struct latitude : coordinate<latitude, double> {
-  using coordinate::coordinate;
-};
+template<typename T = double>
+using longitude = units::dimensionless<units::one, ranged_representation<T, T(-180), T(180)>>;
 
-struct longitude : coordinate<longitude, double> {
-  using coordinate::coordinate;
-};
-
-template<class CharT, class Traits>
-std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os, const latitude& lat)
+template<class CharT, class Traits, typename T>
+std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os, const latitude<T>& lat)
 {
-  if (lat.value() > 0)
-    return os << "N" << lat.value();
+  if (lat.number() > 0)
+    return os << "N" << lat.number();
   else
-    return os << "S" << -lat.value();
+    return os << "S" << -lat.number();
 }
 
-template<class CharT, class Traits>
-std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os, const longitude& lon)
+template<class CharT, class Traits, typename T>
+std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os, const longitude<T>& lon)
 {
-  if (lon.value() > 0)
-    return os << "E" << lon.value();
+  if (lon.number() > 0)
+    return os << "E" << lon.number();
   else
-    return os << "W" << -lon.value();
+    return os << "W" << -lon.number();
 }
 
 inline namespace literals {
 
-constexpr auto operator"" _N(unsigned long long v) { return latitude(static_cast<latitude::value_type>(v)); }
-constexpr auto operator"" _N(long double v) { return latitude(static_cast<latitude::value_type>(v)); }
-constexpr auto operator"" _S(unsigned long long v) { return latitude(-static_cast<latitude::value_type>(v)); }
-constexpr auto operator"" _S(long double v) { return latitude(-static_cast<latitude::value_type>(v)); }
-constexpr auto operator"" _E(unsigned long long v) { return longitude(static_cast<longitude::value_type>(v)); }
-constexpr auto operator"" _E(long double v) { return longitude(static_cast<longitude::value_type>(v)); }
-constexpr auto operator"" _W(unsigned long long v) { return longitude(-static_cast<longitude::value_type>(v)); }
-constexpr auto operator"" _W(long double v) { return longitude(-static_cast<longitude::value_type>(v)); }
+constexpr auto operator"" _N(long double v) { return latitude<long double>(latitude<long double>::rep(v)); }
+constexpr auto operator"" _S(long double v) { return latitude<long double>(latitude<long double>::rep(v)); }
+constexpr auto operator"" _E(long double v) { return longitude<long double>(longitude<long double>::rep(v)); }
+constexpr auto operator"" _W(long double v) { return longitude<long double>(longitude<long double>::rep(v)); }
+constexpr auto operator"" _N(unsigned long long v)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(v));
+  return latitude<std::int64_t>(latitude<std::int64_t>::rep(static_cast<std::int64_t>(v)));
+}
+constexpr auto operator"" _S(unsigned long long v)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(v));
+  return latitude<std::int64_t>(-latitude<std::int64_t>::rep(static_cast<std::int64_t>(v)));
+}
+constexpr auto operator"" _E(unsigned long long v)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(v));
+  return longitude<std::int64_t>(longitude<std::int64_t>::rep(static_cast<std::int64_t>(v)));
+}
+constexpr auto operator"" _W(unsigned long long v)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(v));
+  return longitude<std::int64_t>(-longitude<std::int64_t>::rep(static_cast<std::int64_t>(v)));
+}
 
 }  // namespace literals
 
 }  // namespace geographic
 
-template<>
-class std::numeric_limits<geographic::latitude> : public numeric_limits<geographic::latitude::value_type> {
-  static constexpr auto min() noexcept { return geographic::latitude(-90); }
-  static constexpr auto lowest() noexcept { return geographic::latitude(-90); }
-  static constexpr auto max() noexcept { return geographic::latitude(90); }
+template<typename T>
+class std::numeric_limits<geographic::latitude<T>> : public numeric_limits<T> {
+  static constexpr auto min() noexcept { return geographic::latitude<T>(-90); }
+  static constexpr auto lowest() noexcept { return geographic::latitude<T>(-90); }
+  static constexpr auto max() noexcept { return geographic::latitude<T>(90); }
 };
 
-template<>
-class std::numeric_limits<geographic::longitude> : public numeric_limits<geographic::longitude::value_type> {
-  static constexpr auto min() noexcept { return geographic::longitude(-180); }
-  static constexpr auto lowest() noexcept { return geographic::longitude(-180); }
-  static constexpr auto max() noexcept { return geographic::longitude(180); }
+template<typename T>
+class std::numeric_limits<geographic::longitude<T>> : public numeric_limits<T> {
+  static constexpr auto min() noexcept { return geographic::longitude<T>(-180); }
+  static constexpr auto lowest() noexcept { return geographic::longitude<T>(-180); }
+  static constexpr auto max() noexcept { return geographic::longitude<T>(180); }
 };
 
-template<>
-struct STD_FMT::formatter<geographic::latitude> : formatter<geographic::latitude::value_type> {
+template<typename T>
+struct STD_FMT::formatter<geographic::latitude<T>> : formatter<T> {
   template<typename FormatContext>
-  auto format(geographic::latitude lat, FormatContext& ctx)
+  auto format(geographic::latitude<T> lat, FormatContext& ctx)
   {
-    STD_FMT::format_to(ctx.out(), "{}", lat.value() > 0 ? 'N' : 'S');
-    return formatter<geographic::latitude::value_type>::format(lat.value() > 0 ? lat.value() : -lat.value(), ctx);
+    using rep = geographic::latitude<T>::rep;
+    STD_FMT::format_to(ctx.out(), "{}", lat > rep{0} ? 'N' : 'S');
+    return formatter<T>::format(lat > rep{0} ? lat.number() : -lat.number(), ctx);
   }
 };
 
-template<>
-struct STD_FMT::formatter<geographic::longitude> : formatter<geographic::longitude::value_type> {
+template<typename T>
+struct STD_FMT::formatter<geographic::longitude<T>> : formatter<T> {
   template<typename FormatContext>
-  auto format(geographic::longitude lon, FormatContext& ctx)
+  auto format(geographic::longitude<T> lon, FormatContext& ctx)
   {
-    STD_FMT::format_to(ctx.out(), "{}", lon.value() > 0 ? 'E' : 'W');
-    return formatter<geographic::longitude::value_type>::format(lon.value() > 0 ? lon.value() : -lon.value(), ctx);
+    using rep = geographic::longitude<T>::rep;
+    STD_FMT::format_to(ctx.out(), "{}", lon > rep{0} ? 'E' : 'W');
+    return formatter<T>::format(lon > rep{0} ? lon.number() : -lon.number(), ctx);
   }
 };
 
@@ -124,11 +133,41 @@ namespace geographic {
 struct horizontal_kind : units::kind<horizontal_kind, units::isq::si::dim_length> {};
 using distance = units::quantity_kind<horizontal_kind, units::isq::si::kilometre>;
 
+template<typename T>
 struct position {
-  latitude lat;
-  longitude lon;
+  latitude<T> lat;
+  longitude<T> lon;
 };
 
-distance spherical_distance(position from, position to);
+template<typename T>
+distance spherical_distance(position<T> from, position<T> to)
+{
+  using namespace units::isq::si;
+  constexpr length<kilometre> earth_radius(6371);
+
+  constexpr auto p = std::numbers::pi_v<T> / 180;
+  const auto lat1_rad = from.lat.number() * p;
+  const auto lon1_rad = from.lon.number() * p;
+  const auto lat2_rad = to.lat.number() * p;
+  const auto lon2_rad = to.lon.number() * p;
+
+  using std::sin, std::cos, std::asin, std::acos, std::sqrt;
+
+  // https://en.wikipedia.org/wiki/Great-circle_distance#Formulae
+  if constexpr (sizeof(T) >= 8) {
+    // spherical law of cosines
+    const auto central_angle =
+      acos(sin(lat1_rad) * sin(lat2_rad) + cos(lat1_rad) * cos(lat2_rad) * cos(lon2_rad - lon1_rad));
+    // const auto central_angle = 2 * asin(sqrt(0.5 - cos(lat2_rad - lat1_rad) / 2 + cos(lat1_rad) * cos(lat2_rad) * (1
+    // - cos(lon2_rad - lon1_rad)) / 2));
+    return distance(earth_radius * central_angle);
+  } else {
+    // the haversine formula
+    const auto sin_lat = sin((lat2_rad - lat1_rad) / 2);
+    const auto sin_lon = sin((lon2_rad - lon1_rad) / 2);
+    const auto central_angle = 2 * asin(sqrt(sin_lat * sin_lat + cos(lat1_rad) * cos(lat2_rad) * sin_lon * sin_lon));
+    return distance(earth_radius * central_angle);
+  }
+}
 
 }  // namespace geographic
diff --git a/example/glide_computer/include/glide_computer.h b/example/glide_computer/include/glide_computer.h
index d545ea7a..c515868c 100644
--- a/example/glide_computer/include/glide_computer.h
+++ b/example/glide_computer/include/glide_computer.h
@@ -136,7 +136,7 @@ struct weather {
 
 struct waypoint {
   std::string name;
-  geographic::position pos;
+  geographic::position<long double> pos;
   altitude alt;
 };
 

From c598201d113fb3ae7ca133980fa1701e8157dc2d Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 22 Apr 2022 13:07:01 +0200
Subject: [PATCH 14/68] fix: `ranged_representation` refactored to work with
 older compilers

---
 example/glide_computer/include/geographic.h |  5 +++--
 example/include/ranged_representation.h     | 22 +++++++++------------
 2 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/example/glide_computer/include/geographic.h b/example/glide_computer/include/geographic.h
index e8a56714..9c72b1e0 100644
--- a/example/glide_computer/include/geographic.h
+++ b/example/glide_computer/include/geographic.h
@@ -28,6 +28,7 @@
 #include <units/isq/si/length.h>
 #include <units/quantity_kind.h>
 #include <limits>
+#include <numbers>
 #include <ostream>
 
 // IWYU pragma: begin_exports
@@ -38,10 +39,10 @@ namespace geographic {
 
 // TODO Change to `angle` dimension in degree unit when the work on magnitudes is done
 template<typename T = double>
-using latitude = units::dimensionless<units::one, ranged_representation<T, T(-90), T(90)>>;
+using latitude = units::dimensionless<units::one, ranged_representation<T, -90, 90>>;
 
 template<typename T = double>
-using longitude = units::dimensionless<units::one, ranged_representation<T, T(-180), T(180)>>;
+using longitude = units::dimensionless<units::one, ranged_representation<T, -180, 180>>;
 
 template<class CharT, class Traits, typename T>
 std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os, const latitude<T>& lat)
diff --git a/example/include/ranged_representation.h b/example/include/ranged_representation.h
index 8d5ec234..b620729e 100644
--- a/example/include/ranged_representation.h
+++ b/example/include/ranged_representation.h
@@ -26,27 +26,23 @@
 #include <algorithm>
 #include <type_traits>
 
-template<auto Min, auto Max>
-inline constexpr auto is_in_range = [](const auto& v) { return std::clamp(v, Min, Max) == v; };
+template<typename T, auto Min, auto Max>
+inline constexpr auto is_in_range = [](const auto& v) { return std::clamp(v, T{Min}, T{Max}) == v; };
 
-template<typename T, T Min, T Max>
-class ranged_representation : public validated_type<T, decltype(is_in_range<Min, Max>)> {
+template<typename T, auto Min, auto Max>
+class ranged_representation : public validated_type<T, decltype(is_in_range<T, Min, Max>)> {
 public:
-  using base = validated_type<T, decltype(is_in_range<Min, Max>)>;
+  using base = validated_type<T, decltype(is_in_range<T, Min, Max>)>;
   using base::validated_type;
   constexpr ranged_representation() : base(T{}) {}
 
   [[nodiscard]] constexpr ranged_representation operator-() const { return ranged_representation(-this->value()); }
 };
 
-template<typename T, T Min, T Max>
+template<typename T, auto Min, auto Max>
 struct std::common_type<std::intmax_t, ranged_representation<T, Min, Max>> :
-    std::type_identity<
-      ranged_representation<std::common_type_t<std::intmax_t, T>, std::common_type_t<std::intmax_t, T>{Min},
-                            std::common_type_t<std::intmax_t, T>{Max}>> {};
+    std::type_identity<ranged_representation<std::common_type_t<std::intmax_t, T>, Min, Max>> {};
 
-template<typename T, T Min, T Max>
+template<typename T, auto Min, auto Max>
 struct std::common_type<ranged_representation<T, Min, Max>, std::intmax_t> :
-    std::type_identity<
-      ranged_representation<std::common_type_t<T, std::intmax_t>, std::common_type_t<T, std::intmax_t>{Min},
-                            std::common_type_t<T, std::intmax_t>{Max}>> {};
+    std::type_identity<ranged_representation<std::common_type_t<T, std::intmax_t>, Min, Max>> {};

From 967c1c9ca997c2b1c596d462ba7934f4d92d7d33 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 22 Apr 2022 13:26:31 +0200
Subject: [PATCH 15/68] fix: `ranged_representation` fixed for clang-12

---
 example/include/ranged_representation.h | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/example/include/ranged_representation.h b/example/include/ranged_representation.h
index b620729e..3d7b2a88 100644
--- a/example/include/ranged_representation.h
+++ b/example/include/ranged_representation.h
@@ -23,6 +23,7 @@
 #pragma once
 
 #include "validated_type.h"
+#include <units/bits/external/hacks.h>
 #include <algorithm>
 #include <type_traits>
 
@@ -30,11 +31,13 @@ template<typename T, auto Min, auto Max>
 inline constexpr auto is_in_range = [](const auto& v) { return std::clamp(v, T{Min}, T{Max}) == v; };
 
 template<typename T, auto Min, auto Max>
-class ranged_representation : public validated_type<T, decltype(is_in_range<T, Min, Max>)> {
+using is_in_range_t = decltype(is_in_range<T, Min, Max>);
+
+template<typename T, auto Min, auto Max>
+class ranged_representation : public validated_type<T, is_in_range_t<T, Min, Max>> {
 public:
-  using base = validated_type<T, decltype(is_in_range<T, Min, Max>)>;
-  using base::validated_type;
-  constexpr ranged_representation() : base(T{}) {}
+  using validated_type<T, is_in_range_t<T, Min, Max>>::validated_type;
+  constexpr ranged_representation() : validated_type<T, is_in_range_t<T, Min, Max>>(T{}) {}
 
   [[nodiscard]] constexpr ranged_representation operator-() const { return ranged_representation(-this->value()); }
 };

From 954dc5d53e3735d550c949ae0471122e894b6d74 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 22 Apr 2022 13:27:11 +0200
Subject: [PATCH 16/68] fix: missing `typename` added for clang-12

---
 example/glide_computer/include/geographic.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/example/glide_computer/include/geographic.h b/example/glide_computer/include/geographic.h
index 9c72b1e0..851f79c6 100644
--- a/example/glide_computer/include/geographic.h
+++ b/example/glide_computer/include/geographic.h
@@ -23,6 +23,7 @@
 #pragma once
 
 #include "ranged_representation.h"
+#include <units/bits/external/hacks.h>
 #include <units/bits/fmt_hacks.h>
 #include <units/generic/dimensionless.h>
 #include <units/isq/si/length.h>
@@ -112,7 +113,7 @@ struct STD_FMT::formatter<geographic::latitude<T>> : formatter<T> {
   template<typename FormatContext>
   auto format(geographic::latitude<T> lat, FormatContext& ctx)
   {
-    using rep = geographic::latitude<T>::rep;
+    using rep = TYPENAME geographic::latitude<T>::rep;
     STD_FMT::format_to(ctx.out(), "{}", lat > rep{0} ? 'N' : 'S');
     return formatter<T>::format(lat > rep{0} ? lat.number() : -lat.number(), ctx);
   }
@@ -123,7 +124,7 @@ struct STD_FMT::formatter<geographic::longitude<T>> : formatter<T> {
   template<typename FormatContext>
   auto format(geographic::longitude<T> lon, FormatContext& ctx)
   {
-    using rep = geographic::longitude<T>::rep;
+    using rep = TYPENAME geographic::longitude<T>::rep;
     STD_FMT::format_to(ctx.out(), "{}", lon > rep{0} ? 'E' : 'W');
     return formatter<T>::format(lon > rep{0} ? lon.number() : -lon.number(), ctx);
   }

From e62c162610202748fdf2cf0d04d0e38270c07fa6 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Sat, 23 Apr 2022 16:52:06 +0200
Subject: [PATCH 17/68] fix: `radioactivity` header compilation fixed

---
 .../si/include/units/isq/si/radioactivity.h   | 42 +++++++++----------
 1 file changed, 21 insertions(+), 21 deletions(-)

diff --git a/src/systems/si/include/units/isq/si/radioactivity.h b/src/systems/si/include/units/isq/si/radioactivity.h
index 017d8fcf..7db478d1 100644
--- a/src/systems/si/include/units/isq/si/radioactivity.h
+++ b/src/systems/si/include/units/isq/si/radioactivity.h
@@ -280,47 +280,47 @@ using namespace radioactivity_references;
 namespace units::aliases::isq::si::inline radioactivity {
 
 template<Representation Rep = double>
-using Bq = units::isq::radioactivity<units::isq::becquerel, Rep>;
+using Bq = units::isq::si::radioactivity<units::isq::si::becquerel, Rep>;
 template<Representation Rep = double>
-using yBq = units::isq::radioactivity<units::isq::yoctobecquerel, Rep>;
+using yBq = units::isq::si::radioactivity<units::isq::si::yoctobecquerel, Rep>;
 template<Representation Rep = double>
-using zBq = units::isq::radioactivity<units::isq::zeptobecquerel, Rep>;
+using zBq = units::isq::si::radioactivity<units::isq::si::zeptobecquerel, Rep>;
 template<Representation Rep = double>
-using aBq = units::isq::radioactivity<units::isq::attobecquerel, Rep>;
+using aBq = units::isq::si::radioactivity<units::isq::si::attobecquerel, Rep>;
 template<Representation Rep = double>
-using fBq = units::isq::radioactivity<units::isq::femtobecquerel, Rep>;
+using fBq = units::isq::si::radioactivity<units::isq::si::femtobecquerel, Rep>;
 template<Representation Rep = double>
-using pBq = units::isq::radioactivity<units::isq::picobecquerel, Rep>;
+using pBq = units::isq::si::radioactivity<units::isq::si::picobecquerel, Rep>;
 template<Representation Rep = double>
-using nBq = units::isq::radioactivity<units::isq::nanobecquerel, Rep>;
+using nBq = units::isq::si::radioactivity<units::isq::si::nanobecquerel, Rep>;
 template<Representation Rep = double>
-using uBq = units::isq::radioactivity<units::isq::microbecquerel, Rep>;
+using uBq = units::isq::si::radioactivity<units::isq::si::microbecquerel, Rep>;
 template<Representation Rep = double>
-using mBq = units::isq::radioactivity<units::isq::millibecquerel, Rep>;
+using mBq = units::isq::si::radioactivity<units::isq::si::millibecquerel, Rep>;
 template<Representation Rep = double>
-using cBq = units::isq::radioactivity<units::isq::centibecquerel, Rep>;
+using cBq = units::isq::si::radioactivity<units::isq::si::centibecquerel, Rep>;
 template<Representation Rep = double>
-using dBq = units::isq::radioactivity<units::isq::decibecquerel, Rep>;
+using dBq = units::isq::si::radioactivity<units::isq::si::decibecquerel, Rep>;
 template<Representation Rep = double>
-using daBq = units::isq::radioactivity<units::isq::decabecquerel, Rep>;
+using daBq = units::isq::si::radioactivity<units::isq::si::decabecquerel, Rep>;
 template<Representation Rep = double>
-using hBq = units::isq::radioactivity<units::isq::hectobecquerel, Rep>;
+using hBq = units::isq::si::radioactivity<units::isq::si::hectobecquerel, Rep>;
 template<Representation Rep = double>
-using kBq = units::isq::radioactivity<units::isq::kilobecquerel, Rep>;
+using kBq = units::isq::si::radioactivity<units::isq::si::kilobecquerel, Rep>;
 template<Representation Rep = double>
-using MBq = units::isq::radioactivity<units::isq::megabecquerel, Rep>;
+using MBq = units::isq::si::radioactivity<units::isq::si::megabecquerel, Rep>;
 template<Representation Rep = double>
-using GBq = units::isq::radioactivity<units::isq::gigabecquerel, Rep>;
+using GBq = units::isq::si::radioactivity<units::isq::si::gigabecquerel, Rep>;
 template<Representation Rep = double>
-using TBq = units::isq::radioactivity<units::isq::terabecquerel, Rep>;
+using TBq = units::isq::si::radioactivity<units::isq::si::terabecquerel, Rep>;
 template<Representation Rep = double>
-using PBq = units::isq::radioactivity<units::isq::petabecquerel, Rep>;
+using PBq = units::isq::si::radioactivity<units::isq::si::petabecquerel, Rep>;
 template<Representation Rep = double>
-using EBq = units::isq::radioactivity<units::isq::exabecquerel, Rep>;
+using EBq = units::isq::si::radioactivity<units::isq::si::exabecquerel, Rep>;
 template<Representation Rep = double>
-using ZBq = units::isq::radioactivity<units::isq::zettabecquerel, Rep>;
+using ZBq = units::isq::si::radioactivity<units::isq::si::zettabecquerel, Rep>;
 template<Representation Rep = double>
-using YBq = units::isq::radioactivity<units::isq::yottabecquerel, Rep>;
+using YBq = units::isq::si::radioactivity<units::isq::si::yottabecquerel, Rep>;
 
 }  // namespace units::aliases::isq::si::inline radioactivity
 

From 56cee31a675fe731103421da0570198ed1015a1f Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Sun, 24 Apr 2022 19:52:07 +0200
Subject: [PATCH 18/68] fix: `si::hep::dim_momentum` duplicated definition
 fixed

---
 src/systems/si-hep/include/units/isq/si/hep/momentum.h | 5 +++--
 test/unit_test/static/si_hep_test.cpp                  | 2 --
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/systems/si-hep/include/units/isq/si/hep/momentum.h b/src/systems/si-hep/include/units/isq/si/hep/momentum.h
index 285f9d21..74a85390 100644
--- a/src/systems/si-hep/include/units/isq/si/hep/momentum.h
+++ b/src/systems/si-hep/include/units/isq/si/hep/momentum.h
@@ -24,7 +24,6 @@
 
 // IWYU pragma: begin_exports
 #include <units/isq/dimensions/momentum.h>
-#include <units/isq/si/momentum.h>
 #include <units/quantity.h>
 #include <units/symbol_text.h>
 // IWYU pragma: end_exports
@@ -35,9 +34,11 @@
 
 namespace units::isq::si::hep {
 
+struct kilogram_metre_per_second : unit<kilogram_metre_per_second> {};
+
 struct eV_per_c :
     named_scaled_unit<eV_per_c, "eV/c", prefix, ratio(5'344'285'992'678, 1'000'000'000'000, -35),
-                      ::units::isq::si::kilogram_metre_per_second> {};
+                      kilogram_metre_per_second> {};
 struct feV_per_c : prefixed_unit<feV_per_c, femto, eV_per_c> {};
 struct peV_per_c : prefixed_unit<peV_per_c, pico, eV_per_c> {};
 struct neV_per_c : prefixed_unit<neV_per_c, nano, eV_per_c> {};
diff --git a/test/unit_test/static/si_hep_test.cpp b/test/unit_test/static/si_hep_test.cpp
index 914ceddd..87045e63 100644
--- a/test/unit_test/static/si_hep_test.cpp
+++ b/test/unit_test/static/si_hep_test.cpp
@@ -40,8 +40,6 @@ static_assert(si::mass<si::hep::eV_per_c2>(1'000) == si::hep::mass<si::hep::keV_
 
 // momentum
 static_assert(si::hep::momentum<si::hep::eV_per_c>(1'000'000) == si::hep::momentum<si::hep::MeV_per_c>(1));
-static_assert(si::hep::momentum<si::hep::eV_per_c>(1'000'000) == si::momentum<si::hep::MeV_per_c>(1));
-static_assert(si::momentum<si::hep::eV_per_c>(1'000'000) == si::hep::momentum<si::hep::MeV_per_c>(1));
 
 // area
 static_assert(si::area<si::hep::barn>(1e28) == si::area<si::square_metre>(1));

From 464b4467ee5d291ff72e21721d0a48133ae9883b Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Sun, 24 Apr 2022 19:52:58 +0200
Subject: [PATCH 19/68] fix: public headers fixed to be standalone

---
 src/systems/isq/include/units/isq/dimensions/momentum.h | 1 +
 src/systems/si-hep/include/units/isq/si/hep/area.h      | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/systems/isq/include/units/isq/dimensions/momentum.h b/src/systems/isq/include/units/isq/dimensions/momentum.h
index f7240259..8508fb0a 100644
--- a/src/systems/isq/include/units/isq/dimensions/momentum.h
+++ b/src/systems/isq/include/units/isq/dimensions/momentum.h
@@ -23,6 +23,7 @@
 #pragma once
 
 #include <units/concepts.h>
+#include <units/isq/dimensions/mass.h>
 #include <units/isq/dimensions/speed.h>
 
 namespace units::isq {
diff --git a/src/systems/si-hep/include/units/isq/si/hep/area.h b/src/systems/si-hep/include/units/isq/si/hep/area.h
index 9718fb2d..da988438 100644
--- a/src/systems/si-hep/include/units/isq/si/hep/area.h
+++ b/src/systems/si-hep/include/units/isq/si/hep/area.h
@@ -29,7 +29,7 @@
 #include <units/symbol_text.h>
 // IWYU pragma: end_exports
 
-#include <units/isq/si/length.h>
+#include <units/isq/si/area.h>
 #include <units/unit.h>
 
 namespace units::isq::si::hep {

From d18bf2229a5afd86b018e296c4c6878e9b8f3c8e Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Sun, 24 Apr 2022 19:59:46 +0200
Subject: [PATCH 20/68] test: standalone public headers tests added

---
 CMakeLists.txt                              |  42 ++++++-
 cmake/TestHeaders.cmake                     | 128 ++++++++++++++++++++
 src/CMakeLists.txt                          |   2 +-
 src/cmake/AddUnitsModule.cmake              |  42 ++++++-
 src/core-fmt/CMakeLists.txt                 |   9 +-
 src/core-io/CMakeLists.txt                  |   9 +-
 src/core/CMakeLists.txt                     |  28 ++++-
 src/systems/CMakeLists.txt                  |   2 +-
 src/systems/isq-iec80000/CMakeLists.txt     |  14 ++-
 src/systems/isq-natural/CMakeLists.txt      |  19 ++-
 src/systems/isq/CMakeLists.txt              |  53 +++++++-
 src/systems/si-cgs/CMakeLists.txt           |  19 ++-
 src/systems/si-fps/CMakeLists.txt           |  22 +++-
 src/systems/si-hep/CMakeLists.txt           |  13 +-
 src/systems/si-iau/CMakeLists.txt           |  10 +-
 src/systems/si-imperial/CMakeLists.txt      |  10 +-
 src/systems/si-international/CMakeLists.txt |  14 ++-
 src/systems/si-typographic/CMakeLists.txt   |  11 +-
 src/systems/si-uscs/CMakeLists.txt          |  11 +-
 src/systems/si/CMakeLists.txt               |  55 ++++++++-
 20 files changed, 476 insertions(+), 37 deletions(-)
 create mode 100644 cmake/TestHeaders.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e3626289..00112c6f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -20,7 +20,7 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 project(mp-units-dev LANGUAGES CXX)
 
 list(APPEND CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/cmake")
@@ -71,3 +71,43 @@ add_subdirectory(docs)
 # add unit tests
 enable_testing()
 add_subdirectory(test)
+
+function(get_target_linked_targets target targets_out)
+    get_target_property(linked_libs ${target} INTERFACE_LINK_LIBRARIES)
+    foreach(linked_lib ${linked_libs})
+        if(NOT linked_lib IN_LIST targets)
+            if(TARGET ${linked_lib})
+                get_target_linked_targets(${linked_lib} child_targets)
+                list(APPEND targets ${linked_lib} ${child_targets})
+            endif()
+        endif()
+    endforeach()
+
+    list(REMOVE_DUPLICATES targets)
+    list(REMOVE_DUPLICATES link_libs)
+    set(${targets_out} ${targets} PARENT_SCOPE)
+endfunction()
+
+function(get_target_sources target paths_out)
+    get_target_linked_targets(${target} targets)
+    list(APPEND targets ${target})
+
+    foreach(t ${targets})
+        get_target_property(sources ${t} SOURCES)
+        if(sources)
+            get_target_property(source_dir ${t} SOURCE_DIR)
+            foreach(f ${sources})
+                file(REAL_PATH "${f}" path BASE_DIRECTORY "${source_dir}")
+                list(APPEND paths "${path}")
+            endforeach()
+        endif()
+    endforeach()
+
+    set(${paths_out} ${paths} PARENT_SCOPE)
+endfunction()
+
+# tests for standalone headers
+include(TestHeaders)
+get_target_sources(mp-units::mp-units sources)
+add_header_test(test_headers HEADERS ${sources})
+target_link_libraries(test_headers PRIVATE mp-units::mp-units)
diff --git a/cmake/TestHeaders.cmake b/cmake/TestHeaders.cmake
new file mode 100644
index 00000000..663c9f4e
--- /dev/null
+++ b/cmake/TestHeaders.cmake
@@ -0,0 +1,128 @@
+# Copyright Louis Dionne 2013-2017
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+#
+#
+# This CMake module provides a function generating a unit test to make sure
+# that every public header can be included on its own.
+#
+# When a C++ library or application has many header files, it can happen that
+# a header does not include all the other headers it depends on. When this is
+# the case, it can happen that including that header file on its own will
+# break the compilation. This CMake module generates a dummy executable
+# comprised of many .cpp files, each of which includes a header file that
+# is part of the public API. In other words, the executable is comprised
+# of .cpp files of the form:
+#
+#   #include <the/public/header.hpp>
+#
+# and then exactly one `main` function. If this succeeds to compile, it means
+# that the header can be included on its own, which is what clients expect.
+# Otherwise, you have a problem. Since writing these dumb unit tests by hand
+# is tedious and repetitive, you can use this CMake module to automate this
+# task.
+
+#   add_header_test(<target> [EXCLUDE_FROM_ALL] [EXCLUDE excludes...] HEADERS headers...)
+#
+# Generates header-inclusion unit tests for all the specified headers.
+#
+# This function creates a target which builds a dummy executable including
+# each specified header file individually. If this target builds successfully,
+# it means that all the specified header files can be included individually.
+#
+# Parameters
+# ----------
+# <target>:
+#   The name of the target to generate.
+#
+# HEADERS headers:
+#   A list of header files to generate the inclusion tests for. All headers
+#   in this list must be represented as relative paths from the root of the
+#   include directory added to the compiler's header search path. In other
+#   words, it should be possible to include all headers in this list as
+#
+#       #include <${header}>
+#
+#   For example, for a library with the following structure:
+#
+#       project/
+#           doc/
+#           test/
+#           ...
+#           include/
+#               boost/
+#                   hana.hpp
+#                   hana/
+#                       transform.hpp
+#                       tuple.hpp
+#                       pair.hpp
+#                       ...
+#
+#   When building the unit tests for that library, we'll add `-I project/include'
+#   to the compiler's arguments. The list of public headers should therefore contain
+#
+#       boost/hana.hpp
+#       boost/hana/transform.hpp
+#       boost/hana/tuple.hpp
+#       boost/hana/pair.hpp
+#       ...
+#
+#   Usually, all the 'public' header files of a library should be tested for
+#   standalone inclusion. A header is considered 'public' if a client should
+#   be able to include that header on its own.
+#
+# [EXCLUDE excludes]:
+#   An optional list of headers or regexes for which no unit test should be
+#   generated. Basically, any header in the list specified by the `HEADERS`
+#   argument that matches anything in `EXCLUDE` will be skipped.
+#
+# [EXCLUDE_FROM_ALL]:
+#   If provided, the generated target is excluded from the 'all' target.
+#
+function(add_header_test target)
+    cmake_parse_arguments(ARGS "EXCLUDE_FROM_ALL"             # options
+                               ""                             # 1 value args
+                               "HEADERS;EXCLUDE"              # multivalued args
+                               ${ARGN})
+    if (NOT ARGS_HEADERS)
+        message(FATAL_ERROR "The `HEADERS` argument must be provided.")
+    endif()
+
+    if (ARGS_EXCLUDE_FROM_ALL)
+        set(ARGS_EXCLUDE_FROM_ALL "EXCLUDE_FROM_ALL")
+    else()
+        set(ARGS_EXCLUDE_FROM_ALL "")
+    endif()
+
+    foreach(header ${ARGS_HEADERS})
+        set(skip FALSE)
+        foreach(exclude ${ARGS_EXCLUDE})
+            if (${header} MATCHES ${exclude})
+                set(skip TRUE)
+                break()
+            endif()
+        endforeach()
+        if (skip)
+            continue()
+        endif()
+
+        get_filename_component(filename "${header}" NAME_WE)
+        get_filename_component(directory "${header}" DIRECTORY)
+
+        set(source "${CMAKE_CURRENT_BINARY_DIR}/headers/${directory}/${filename}.cpp")
+        if (NOT EXISTS "${source}")
+            file(WRITE "${source}" "#include <${header}>")
+        endif()
+        list(APPEND sources "${source}")
+    endforeach()
+
+    set(standalone_main "${CMAKE_CURRENT_BINARY_DIR}/headers/_standalone_main.cpp")
+    if (NOT EXISTS "${standalone_main}")
+        file(WRITE "${standalone_main}" "int main() { }")
+    endif()
+    add_executable(${target}
+        ${ARGS_EXCLUDE_FROM_ALL}
+        ${sources}
+        "${CMAKE_CURRENT_BINARY_DIR}/headers/_standalone_main.cpp"
+    )
+endfunction()
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 4ed41451..32a5e555 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -20,7 +20,7 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 project(mp-units VERSION 0.8.0 LANGUAGES CXX)
 
 set(projectPrefix UNITS_)
diff --git a/src/cmake/AddUnitsModule.cmake b/src/cmake/AddUnitsModule.cmake
index bac9a57d..2f92d92b 100644
--- a/src/cmake/AddUnitsModule.cmake
+++ b/src/cmake/AddUnitsModule.cmake
@@ -20,14 +20,48 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
+
+function(validate_unparsed module prefix)
+    if(${prefix}_UNPARSED_ARGUMENTS)
+        message(FATAL_ERROR "Invalid arguments '${${prefix}_UNPARSED_ARGUMENTS}' "
+            "for module '${module}'")
+    endif()
+endfunction()
+
+function(validate_argument_exists module prefix arg)
+    if(NOT ${prefix}_${arg})
+        message(FATAL_ERROR "'${arg}' not provided for module '${module}'")
+    endif()
+endfunction()
+
+function(validate_arguments_exists module prefix)
+    foreach(arg ${ARGN})
+        validate_argument_exists(${module} ${prefix} ${arg})
+    endforeach()
+endfunction()
 
 #
-# add_units_module(ModuleName <depependencies>...)
+# add_units_module(ModuleName
+#                  DEPENDENCIES <depependency>...
+#                  HEADERS <header_file>...)
 #
 function(add_units_module name)
-    add_library(mp-units-${name} INTERFACE)
-    target_link_libraries(mp-units-${name} INTERFACE ${ARGN})
+    # parse arguments
+    set(multiValues DEPENDENCIES HEADERS)
+    cmake_parse_arguments(
+        PARSE_ARGV 1
+        ARG
+        "" "" "${multiValues}"
+    )
+
+    # validate and process arguments
+    validate_unparsed(${name} ARG)
+    validate_arguments_exists(${name} ARG DEPENDENCIES HEADERS)
+
+    # define the target for a module
+    add_library(mp-units-${name} INTERFACE ${ARG_HEADERS})
+    target_link_libraries(mp-units-${name} INTERFACE ${ARG_DEPENDENCIES})
     target_include_directories(
         mp-units-${name} ${unitsAsSystem} INTERFACE $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
                                                     $<INSTALL_INTERFACE:include>
diff --git a/src/core-fmt/CMakeLists.txt b/src/core-fmt/CMakeLists.txt
index 1ee5e6f7..57212995 100644
--- a/src/core-fmt/CMakeLists.txt
+++ b/src/core-fmt/CMakeLists.txt
@@ -20,12 +20,17 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
 option(${projectPrefix}USE_LIBFMT "Enables usage of libfmt instead of the one from 'std'" ON)
 message(STATUS "${projectPrefix}USE_LIBFMT: ${${projectPrefix}USE_LIBFMT}")
 
-add_units_module(core-fmt mp-units::core)
+add_units_module(core-fmt
+    DEPENDENCIES
+        mp-units::core
+    HEADERS
+        include/units/format.h
+)
 target_compile_definitions(mp-units-core-fmt INTERFACE ${projectPrefix}USE_LIBFMT=$<BOOL:${${projectPrefix}USE_LIBFMT}>)
 
 if(${projectPrefix}USE_LIBFMT)
diff --git a/src/core-io/CMakeLists.txt b/src/core-io/CMakeLists.txt
index dc34d127..6faab9ff 100644
--- a/src/core-io/CMakeLists.txt
+++ b/src/core-io/CMakeLists.txt
@@ -20,6 +20,11 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
-add_units_module(core-io mp-units::core)
+add_units_module(core-io
+    DEPENDENCIES
+        mp-units::core
+    HEADERS
+        include/units/quantity_io.h
+)
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index 4a4682be..cdc1eb36 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -20,7 +20,7 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
 # core library options
 set(${projectPrefix}DOWNCAST_MODE ON CACHE STRING "Select downcasting mode")
@@ -34,7 +34,31 @@ include(CheckLibcxxInUse)
 check_libcxx_in_use(${projectPrefix}LIBCXX)
 
 # core library definition
-add_library(mp-units-core INTERFACE)
+add_library(mp-units-core INTERFACE
+    include/units/base_dimension.h
+    include/units/chrono.h
+    include/units/concepts.h
+    include/units/customization_points.h
+    include/units/derived_dimension.h
+    include/units/exponent.h
+    include/units/generic/angle.h
+    include/units/generic/dimensionless.h
+    include/units/kind.h
+    include/units/magnitude.h
+    include/units/math.h
+    include/units/point_origin.h
+    include/units/prefix.h
+    include/units/quantity.h
+    include/units/quantity_cast.h
+    include/units/quantity_kind.h
+    include/units/quantity_point.h
+    include/units/quantity_point_kind.h
+    include/units/random.h
+    include/units/ratio.h
+    include/units/reference.h
+    include/units/symbol_text.h
+    include/units/unit.h
+)
 target_compile_features(mp-units-core INTERFACE cxx_std_20)
 target_link_libraries(mp-units-core INTERFACE gsl::gsl-lite)
 target_include_directories(
diff --git a/src/systems/CMakeLists.txt b/src/systems/CMakeLists.txt
index 41adc78e..06a3169d 100644
--- a/src/systems/CMakeLists.txt
+++ b/src/systems/CMakeLists.txt
@@ -20,7 +20,7 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
 # systems
 add_subdirectory(isq)
diff --git a/src/systems/isq-iec80000/CMakeLists.txt b/src/systems/isq-iec80000/CMakeLists.txt
index 9f37c6f6..84e8f8d7 100644
--- a/src/systems/isq-iec80000/CMakeLists.txt
+++ b/src/systems/isq-iec80000/CMakeLists.txt
@@ -20,6 +20,16 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
-add_units_module(isq-iec80000 mp-units::si)
+add_units_module(isq-iec80000
+    DEPENDENCIES
+        mp-units::si
+    HEADERS
+        include/units/isq/iec80000/binary_prefixes.h
+        include/units/isq/iec80000/iec80000.h
+        include/units/isq/iec80000/modulation_rate.h
+        include/units/isq/iec80000/storage_capacity.h
+        include/units/isq/iec80000/traffic_intensity.h
+        include/units/isq/iec80000/transfer_rate.h
+)
diff --git a/src/systems/isq-natural/CMakeLists.txt b/src/systems/isq-natural/CMakeLists.txt
index 7f9353b4..b88038ce 100644
--- a/src/systems/isq-natural/CMakeLists.txt
+++ b/src/systems/isq-natural/CMakeLists.txt
@@ -20,6 +20,21 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
-add_units_module(isq-natural mp-units::isq)
+add_units_module(isq-natural
+    DEPENDENCIES
+        mp-units::isq
+    HEADERS
+        include/units/isq/natural/acceleration.h
+        include/units/isq/natural/constants.h
+        include/units/isq/natural/energy.h
+        include/units/isq/natural/force.h
+        include/units/isq/natural/length.h
+        include/units/isq/natural/mass.h
+        include/units/isq/natural/momentum.h
+        include/units/isq/natural/natural.h
+        include/units/isq/natural/speed.h
+        include/units/isq/natural/time.h
+        include/units/isq/natural/units.h
+)
diff --git a/src/systems/isq/CMakeLists.txt b/src/systems/isq/CMakeLists.txt
index 1c8e49b5..960a0114 100644
--- a/src/systems/isq/CMakeLists.txt
+++ b/src/systems/isq/CMakeLists.txt
@@ -20,6 +20,55 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
-add_units_module(isq mp-units::core)
+add_units_module(isq
+    DEPENDENCIES
+        mp-units::core
+    HEADERS
+        include/units/isq/dimensions/absorbed_dose.h
+        include/units/isq/dimensions/acceleration.h
+        include/units/isq/dimensions/amount_of_substance.h
+        include/units/isq/dimensions/angular_velocity.h
+        include/units/isq/dimensions/area.h
+        include/units/isq/dimensions/capacitance.h
+        include/units/isq/dimensions/catalytic_activity.h
+        include/units/isq/dimensions/charge_density.h
+        include/units/isq/dimensions/concentration.h
+        include/units/isq/dimensions/conductance.h
+        include/units/isq/dimensions/current_density.h
+        include/units/isq/dimensions/density.h
+        include/units/isq/dimensions/dynamic_viscosity.h
+        include/units/isq/dimensions/electric_charge.h
+        include/units/isq/dimensions/electric_current.h
+        include/units/isq/dimensions/electric_field_strength.h
+        include/units/isq/dimensions/energy.h
+        include/units/isq/dimensions/energy_density.h
+        include/units/isq/dimensions/force.h
+        include/units/isq/dimensions/frequency.h
+        include/units/isq/dimensions/heat_capacity.h
+        include/units/isq/dimensions/inductance.h
+        include/units/isq/dimensions/length.h
+        include/units/isq/dimensions/luminance.h
+        include/units/isq/dimensions/luminous_intensity.h
+        include/units/isq/dimensions/magnetic_flux.h
+        include/units/isq/dimensions/magnetic_induction.h
+        include/units/isq/dimensions/mass.h
+        include/units/isq/dimensions/molar_energy.h
+        include/units/isq/dimensions/momentum.h
+        include/units/isq/dimensions/permeability.h
+        include/units/isq/dimensions/permittivity.h
+        include/units/isq/dimensions/power.h
+        include/units/isq/dimensions/pressure.h
+        include/units/isq/dimensions/radioactivity.h
+        include/units/isq/dimensions/resistance.h
+        include/units/isq/dimensions/speed.h
+        include/units/isq/dimensions/surface_tension.h
+        include/units/isq/dimensions/thermal_conductivity.h
+        include/units/isq/dimensions/thermodynamic_temperature.h
+        include/units/isq/dimensions/time.h
+        include/units/isq/dimensions/torque.h
+        include/units/isq/dimensions/voltage.h
+        include/units/isq/dimensions/volume.h
+        include/units/isq/dimensions.h
+)
diff --git a/src/systems/si-cgs/CMakeLists.txt b/src/systems/si-cgs/CMakeLists.txt
index 10b16ae9..5a1cb20a 100644
--- a/src/systems/si-cgs/CMakeLists.txt
+++ b/src/systems/si-cgs/CMakeLists.txt
@@ -20,6 +20,21 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-cgs mp-units::si)
+add_units_module(si-cgs
+    DEPENDENCIES
+        mp-units::si
+    HEADERS
+        include/units/isq/si/cgs/acceleration.h
+        include/units/isq/si/cgs/area.h
+        include/units/isq/si/cgs/cgs.h
+        include/units/isq/si/cgs/energy.h
+        include/units/isq/si/cgs/force.h
+        include/units/isq/si/cgs/length.h
+        include/units/isq/si/cgs/mass.h
+        include/units/isq/si/cgs/power.h
+        include/units/isq/si/cgs/pressure.h
+        include/units/isq/si/cgs/speed.h
+        include/units/isq/si/cgs/time.h
+)
diff --git a/src/systems/si-fps/CMakeLists.txt b/src/systems/si-fps/CMakeLists.txt
index c311fb5e..12f9bd9e 100644
--- a/src/systems/si-fps/CMakeLists.txt
+++ b/src/systems/si-fps/CMakeLists.txt
@@ -20,6 +20,24 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
+
+add_units_module(si-fps
+    DEPENDENCIES
+        mp-units::si
+    HEADERS
+        include/units/isq/si/fps/acceleration.h
+        include/units/isq/si/fps/area.h
+        include/units/isq/si/fps/density.h
+        include/units/isq/si/fps/energy.h
+        include/units/isq/si/fps/force.h
+        include/units/isq/si/fps/fps.h
+        include/units/isq/si/fps/length.h
+        include/units/isq/si/fps/mass.h
+        include/units/isq/si/fps/power.h
+        include/units/isq/si/fps/pressure.h
+        include/units/isq/si/fps/speed.h
+        include/units/isq/si/fps/time.h
+        include/units/isq/si/fps/volume.h
+)
 
-add_units_module(si-fps mp-units::si)
diff --git a/src/systems/si-hep/CMakeLists.txt b/src/systems/si-hep/CMakeLists.txt
index 0403a82b..66747172 100644
--- a/src/systems/si-hep/CMakeLists.txt
+++ b/src/systems/si-hep/CMakeLists.txt
@@ -20,6 +20,15 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-hep mp-units::si)
+add_units_module(si-hep
+    DEPENDENCIES
+        mp-units::si
+    HEADERS
+        include/units/isq/si/hep/area.h
+        include/units/isq/si/hep/energy.h
+        include/units/isq/si/hep/hep.h
+        include/units/isq/si/hep/mass.h
+        include/units/isq/si/hep/momentum.h
+)
diff --git a/src/systems/si-iau/CMakeLists.txt b/src/systems/si-iau/CMakeLists.txt
index ce9984a8..2677a344 100644
--- a/src/systems/si-iau/CMakeLists.txt
+++ b/src/systems/si-iau/CMakeLists.txt
@@ -20,6 +20,12 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-iau mp-units::si)
+add_units_module(si-iau
+    DEPENDENCIES
+        mp-units::si
+    HEADERS
+        include/units/isq/si/iau/iau.h
+        include/units/isq/si/iau/length.h
+)
diff --git a/src/systems/si-imperial/CMakeLists.txt b/src/systems/si-imperial/CMakeLists.txt
index f99f274b..ac903b82 100644
--- a/src/systems/si-imperial/CMakeLists.txt
+++ b/src/systems/si-imperial/CMakeLists.txt
@@ -20,6 +20,12 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-imperial mp-units::si)
+add_units_module(si-imperial
+    DEPENDENCIES
+        mp-units::si
+    HEADERS
+        include/units/isq/si/imperial/imperial.h
+        include/units/isq/si/imperial/length.h
+)
diff --git a/src/systems/si-international/CMakeLists.txt b/src/systems/si-international/CMakeLists.txt
index e8b2716a..b62cd360 100644
--- a/src/systems/si-international/CMakeLists.txt
+++ b/src/systems/si-international/CMakeLists.txt
@@ -20,6 +20,16 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
+
+add_units_module(si-international
+    DEPENDENCIES
+        mp-units::si
+    HEADERS
+        include/units/isq/si/international/area.h
+        include/units/isq/si/international/international.h
+        include/units/isq/si/international/length.h
+        include/units/isq/si/international/speed.h
+        include/units/isq/si/international/volume.h
+)
 
-add_units_module(si-international mp-units::si)
diff --git a/src/systems/si-typographic/CMakeLists.txt b/src/systems/si-typographic/CMakeLists.txt
index 10d0e4d7..e8d17a84 100644
--- a/src/systems/si-typographic/CMakeLists.txt
+++ b/src/systems/si-typographic/CMakeLists.txt
@@ -20,6 +20,13 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
+
+add_units_module(si-typographic
+    DEPENDENCIES
+        mp-units::si
+    HEADERS
+        include/units/isq/si/typographic/length.h
+        include/units/isq/si/typographic/typographic.h
+)
 
-add_units_module(si-typographic mp-units::si)
diff --git a/src/systems/si-uscs/CMakeLists.txt b/src/systems/si-uscs/CMakeLists.txt
index d5abf74c..4bce00eb 100644
--- a/src/systems/si-uscs/CMakeLists.txt
+++ b/src/systems/si-uscs/CMakeLists.txt
@@ -20,6 +20,13 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
+
+add_units_module(si-uscs
+    DEPENDENCIES
+        mp-units::si
+    HEADERS
+        include/units/isq/si/uscs/length.h
+        include/units/isq/si/uscs/uscs.h
+)
 
-add_units_module(si-uscs mp-units::si)
diff --git a/src/systems/si/CMakeLists.txt b/src/systems/si/CMakeLists.txt
index bb5098b5..5fd34835 100644
--- a/src/systems/si/CMakeLists.txt
+++ b/src/systems/si/CMakeLists.txt
@@ -20,6 +20,57 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si mp-units::isq)
+add_units_module(si
+    DEPENDENCIES
+        mp-units::isq
+    HEADERS
+        include/units/isq/si/absorbed_dose.h
+        include/units/isq/si/acceleration.h
+        include/units/isq/si/amount_of_substance.h
+        include/units/isq/si/angular_velocity.h
+        include/units/isq/si/area.h
+        include/units/isq/si/capacitance.h
+        include/units/isq/si/catalytic_activity.h
+        include/units/isq/si/charge_density.h
+        include/units/isq/si/concentration.h
+        include/units/isq/si/conductance.h
+        include/units/isq/si/constants.h
+        include/units/isq/si/current_density.h
+        include/units/isq/si/density.h
+        include/units/isq/si/dynamic_viscosity.h
+        include/units/isq/si/electric_charge.h
+        include/units/isq/si/electric_current.h
+        include/units/isq/si/electric_field_strength.h
+        include/units/isq/si/energy.h
+        include/units/isq/si/energy_density.h
+        include/units/isq/si/force.h
+        include/units/isq/si/frequency.h
+        include/units/isq/si/heat_capacity.h
+        include/units/isq/si/inductance.h
+        include/units/isq/si/length.h
+        include/units/isq/si/luminance.h
+        include/units/isq/si/luminous_intensity.h
+        include/units/isq/si/magnetic_flux.h
+        include/units/isq/si/magnetic_induction.h
+        include/units/isq/si/mass.h
+        include/units/isq/si/molar_energy.h
+        include/units/isq/si/momentum.h
+        include/units/isq/si/permeability.h
+        include/units/isq/si/permittivity.h
+        include/units/isq/si/power.h
+        include/units/isq/si/prefixes.h
+        include/units/isq/si/pressure.h
+        include/units/isq/si/radioactivity.h
+        include/units/isq/si/resistance.h
+        include/units/isq/si/si.h
+        include/units/isq/si/speed.h
+        include/units/isq/si/surface_tension.h
+        include/units/isq/si/thermal_conductivity.h
+        include/units/isq/si/thermodynamic_temperature.h
+        include/units/isq/si/time.h
+        include/units/isq/si/torque.h
+        include/units/isq/si/voltage.h
+        include/units/isq/si/volume.h
+)

From be678e8ffa4aea9400399432c6d601e3b06926ec Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Sun, 24 Apr 2022 22:23:16 +0200
Subject: [PATCH 21/68] build: `add_public_header_test()` added and fixed
 Windows absolute header path issue

---
 CMakeLists.txt                | 47 +++++-------------------
 cmake/TestPublicHeaders.cmake | 68 +++++++++++++++++++++++++++++++++++
 2 files changed, 77 insertions(+), 38 deletions(-)
 create mode 100644 cmake/TestPublicHeaders.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 00112c6f..cbee492f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -57,6 +57,13 @@ if(${projectPrefix}IWYU)
     endif()
 endif()
 
+option(${projectPrefix}CLANG_TIDY "Enables clang-tidy" OFF)
+if(${projectPrefix}CLANG_TIDY)
+    message(STATUS "Enabling clang-tidy")
+    set(CMAKE_CXX_CLANG_TIDY clang-tidy)
+    message(STATUS "Enabling clang-tidy - done")
+endif()
+
 #enable_clang_tidy()
 
 # add project code
@@ -72,42 +79,6 @@ add_subdirectory(docs)
 enable_testing()
 add_subdirectory(test)
 
-function(get_target_linked_targets target targets_out)
-    get_target_property(linked_libs ${target} INTERFACE_LINK_LIBRARIES)
-    foreach(linked_lib ${linked_libs})
-        if(NOT linked_lib IN_LIST targets)
-            if(TARGET ${linked_lib})
-                get_target_linked_targets(${linked_lib} child_targets)
-                list(APPEND targets ${linked_lib} ${child_targets})
-            endif()
-        endif()
-    endforeach()
-
-    list(REMOVE_DUPLICATES targets)
-    list(REMOVE_DUPLICATES link_libs)
-    set(${targets_out} ${targets} PARENT_SCOPE)
-endfunction()
-
-function(get_target_sources target paths_out)
-    get_target_linked_targets(${target} targets)
-    list(APPEND targets ${target})
-
-    foreach(t ${targets})
-        get_target_property(sources ${t} SOURCES)
-        if(sources)
-            get_target_property(source_dir ${t} SOURCE_DIR)
-            foreach(f ${sources})
-                file(REAL_PATH "${f}" path BASE_DIRECTORY "${source_dir}")
-                list(APPEND paths "${path}")
-            endforeach()
-        endif()
-    endforeach()
-
-    set(${paths_out} ${paths} PARENT_SCOPE)
-endfunction()
-
 # tests for standalone headers
-include(TestHeaders)
-get_target_sources(mp-units::mp-units sources)
-add_header_test(test_headers HEADERS ${sources})
-target_link_libraries(test_headers PRIVATE mp-units::mp-units)
+include(TestPublicHeaders)
+add_public_header_test(test_headers mp-units::mp-units)
diff --git a/cmake/TestPublicHeaders.cmake b/cmake/TestPublicHeaders.cmake
new file mode 100644
index 00000000..a1d3d4a8
--- /dev/null
+++ b/cmake/TestPublicHeaders.cmake
@@ -0,0 +1,68 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2018 Mateusz Pusz
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+cmake_minimum_required(VERSION 3.19)
+
+function(get_target_linked_targets target targets_out)
+    get_target_property(linked_libs ${target} INTERFACE_LINK_LIBRARIES)
+    foreach(linked_lib ${linked_libs})
+        if(NOT linked_lib IN_LIST targets)
+            if(TARGET ${linked_lib})
+                get_target_linked_targets(${linked_lib} child_targets)
+                list(APPEND targets ${linked_lib} ${child_targets})
+            endif()
+        endif()
+    endforeach()
+
+    list(REMOVE_DUPLICATES targets)
+    list(REMOVE_DUPLICATES link_libs)
+    set(${targets_out} ${targets} PARENT_SCOPE)
+endfunction()
+
+function(get_target_sources target paths_out)
+    get_target_linked_targets(${target} targets)
+    list(APPEND targets ${target})
+
+    foreach(t ${targets})
+        get_target_property(sources ${t} SOURCES)
+        if(sources)
+            get_target_property(source_dir ${t} SOURCE_DIR)
+            foreach(f ${sources})
+                file(REAL_PATH "${f}" path BASE_DIRECTORY "${source_dir}")
+                file(RELATIVE_PATH path ${CMAKE_CURRENT_LIST_DIR} "${path}")
+                list(APPEND paths "${path}")
+            endforeach()
+        endif()
+    endforeach()
+
+    set(${paths_out} ${paths} PARENT_SCOPE)
+endfunction()
+
+include(TestHeaders)
+
+function(add_public_header_test target test_target)
+    get_target_sources(${test_target} sources)
+    add_header_test(${target} HEADERS ${sources})
+    target_link_libraries(${target} PRIVATE ${test_target})
+    target_include_directories(${target} PRIVATE .)
+endfunction()
+

From 98da140fae4d266cb5e329f8d7d4d7dcfd8cf89f Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Sun, 24 Apr 2022 22:55:30 +0200
Subject: [PATCH 22/68] ci: `pre-commit` cmake-format checks fixed

---
 .cmake-format.yaml                          |  14 ++-
 cmake/TestHeaders.cmake                     |  29 +++---
 cmake/TestPublicHeaders.cmake               |   1 -
 src/cmake/AddUnitsModule.cmake              |   9 +-
 src/core-fmt/CMakeLists.txt                 |   7 +-
 src/core-io/CMakeLists.txt                  |   7 +-
 src/core/CMakeLists.txt                     |   4 +-
 src/systems/isq-iec80000/CMakeLists.txt     |  16 ++--
 src/systems/isq-natural/CMakeLists.txt      |  29 +++---
 src/systems/isq/CMakeLists.txt              |  97 ++++++++++---------
 src/systems/si-cgs/CMakeLists.txt           |  29 +++---
 src/systems/si-fps/CMakeLists.txt           |  34 ++++---
 src/systems/si-hep/CMakeLists.txt           |  13 +--
 src/systems/si-iau/CMakeLists.txt           |   8 +-
 src/systems/si-imperial/CMakeLists.txt      |   9 +-
 src/systems/si-international/CMakeLists.txt |  16 ++--
 src/systems/si-typographic/CMakeLists.txt   |  10 +-
 src/systems/si-uscs/CMakeLists.txt          |   9 +-
 src/systems/si/CMakeLists.txt               | 101 ++++++++++----------
 19 files changed, 200 insertions(+), 242 deletions(-)

diff --git a/.cmake-format.yaml b/.cmake-format.yaml
index 45da65a4..2956b76e 100644
--- a/.cmake-format.yaml
+++ b/.cmake-format.yaml
@@ -4,19 +4,25 @@ parse:
       pargs:
         nargs: 1
         flags:
-        - ALL
+          - ALL
       kwargs:
         BREATHE_PROJECT: 1
         CODE_SOURCE_DIR: 1
         INSTALL_DIR: 1
         CODE_DEPENDS: 1
         DOCS_DEPENDS: 1
+    add_units_module:
+      pargs:
+        nargs: 1
+      kwargs:
+        DEPENDENCIES: +
+        HEADERS: +
     enable_iwyu:
       pargs:
         flags:
-        - NO_FORWARD_DECLARATIONS
-        - QUOTED_INCLUDES_FIRST
-        - NO_COMMENTS
+          - NO_FORWARD_DECLARATIONS
+          - QUOTED_INCLUDES_FIRST
+          - NO_COMMENTS
       kwargs:
         MAPPING_FILE: 1
         MAX_LINE_LENGTH: 1
diff --git a/cmake/TestHeaders.cmake b/cmake/TestHeaders.cmake
index 663c9f4e..6ec30990 100644
--- a/cmake/TestHeaders.cmake
+++ b/cmake/TestHeaders.cmake
@@ -80,15 +80,18 @@
 #   If provided, the generated target is excluded from the 'all' target.
 #
 function(add_header_test target)
-    cmake_parse_arguments(ARGS "EXCLUDE_FROM_ALL"             # options
-                               ""                             # 1 value args
-                               "HEADERS;EXCLUDE"              # multivalued args
-                               ${ARGN})
-    if (NOT ARGS_HEADERS)
+    cmake_parse_arguments(
+        ARGS
+        "EXCLUDE_FROM_ALL" # options
+        "" # 1 value args
+        "HEADERS;EXCLUDE" # multivalued args
+        ${ARGN}
+    )
+    if(NOT ARGS_HEADERS)
         message(FATAL_ERROR "The `HEADERS` argument must be provided.")
     endif()
 
-    if (ARGS_EXCLUDE_FROM_ALL)
+    if(ARGS_EXCLUDE_FROM_ALL)
         set(ARGS_EXCLUDE_FROM_ALL "EXCLUDE_FROM_ALL")
     else()
         set(ARGS_EXCLUDE_FROM_ALL "")
@@ -97,12 +100,12 @@ function(add_header_test target)
     foreach(header ${ARGS_HEADERS})
         set(skip FALSE)
         foreach(exclude ${ARGS_EXCLUDE})
-            if (${header} MATCHES ${exclude})
+            if(${header} MATCHES ${exclude})
                 set(skip TRUE)
                 break()
             endif()
         endforeach()
-        if (skip)
+        if(skip)
             continue()
         endif()
 
@@ -110,19 +113,17 @@ function(add_header_test target)
         get_filename_component(directory "${header}" DIRECTORY)
 
         set(source "${CMAKE_CURRENT_BINARY_DIR}/headers/${directory}/${filename}.cpp")
-        if (NOT EXISTS "${source}")
+        if(NOT EXISTS "${source}")
             file(WRITE "${source}" "#include <${header}>")
         endif()
         list(APPEND sources "${source}")
     endforeach()
 
     set(standalone_main "${CMAKE_CURRENT_BINARY_DIR}/headers/_standalone_main.cpp")
-    if (NOT EXISTS "${standalone_main}")
+    if(NOT EXISTS "${standalone_main}")
         file(WRITE "${standalone_main}" "int main() { }")
     endif()
-    add_executable(${target}
-        ${ARGS_EXCLUDE_FROM_ALL}
-        ${sources}
-        "${CMAKE_CURRENT_BINARY_DIR}/headers/_standalone_main.cpp"
+    add_executable(
+        ${target} ${ARGS_EXCLUDE_FROM_ALL} ${sources} "${CMAKE_CURRENT_BINARY_DIR}/headers/_standalone_main.cpp"
     )
 endfunction()
diff --git a/cmake/TestPublicHeaders.cmake b/cmake/TestPublicHeaders.cmake
index a1d3d4a8..e1756af5 100644
--- a/cmake/TestPublicHeaders.cmake
+++ b/cmake/TestPublicHeaders.cmake
@@ -65,4 +65,3 @@ function(add_public_header_test target test_target)
     target_link_libraries(${target} PRIVATE ${test_target})
     target_include_directories(${target} PRIVATE .)
 endfunction()
-
diff --git a/src/cmake/AddUnitsModule.cmake b/src/cmake/AddUnitsModule.cmake
index 2f92d92b..7e52697b 100644
--- a/src/cmake/AddUnitsModule.cmake
+++ b/src/cmake/AddUnitsModule.cmake
@@ -24,8 +24,7 @@ cmake_minimum_required(VERSION 3.19)
 
 function(validate_unparsed module prefix)
     if(${prefix}_UNPARSED_ARGUMENTS)
-        message(FATAL_ERROR "Invalid arguments '${${prefix}_UNPARSED_ARGUMENTS}' "
-            "for module '${module}'")
+        message(FATAL_ERROR "Invalid arguments '${${prefix}_UNPARSED_ARGUMENTS}' " "for module '${module}'")
     endif()
 endfunction()
 
@@ -49,11 +48,7 @@ endfunction()
 function(add_units_module name)
     # parse arguments
     set(multiValues DEPENDENCIES HEADERS)
-    cmake_parse_arguments(
-        PARSE_ARGV 1
-        ARG
-        "" "" "${multiValues}"
-    )
+    cmake_parse_arguments(PARSE_ARGV 1 ARG "" "" "${multiValues}")
 
     # validate and process arguments
     validate_unparsed(${name} ARG)
diff --git a/src/core-fmt/CMakeLists.txt b/src/core-fmt/CMakeLists.txt
index 57212995..d88d23f4 100644
--- a/src/core-fmt/CMakeLists.txt
+++ b/src/core-fmt/CMakeLists.txt
@@ -25,12 +25,7 @@ cmake_minimum_required(VERSION 3.19)
 option(${projectPrefix}USE_LIBFMT "Enables usage of libfmt instead of the one from 'std'" ON)
 message(STATUS "${projectPrefix}USE_LIBFMT: ${${projectPrefix}USE_LIBFMT}")
 
-add_units_module(core-fmt
-    DEPENDENCIES
-        mp-units::core
-    HEADERS
-        include/units/format.h
-)
+add_units_module(core-fmt DEPENDENCIES mp-units::core HEADERS include/units/format.h)
 target_compile_definitions(mp-units-core-fmt INTERFACE ${projectPrefix}USE_LIBFMT=$<BOOL:${${projectPrefix}USE_LIBFMT}>)
 
 if(${projectPrefix}USE_LIBFMT)
diff --git a/src/core-io/CMakeLists.txt b/src/core-io/CMakeLists.txt
index 6faab9ff..de797acf 100644
--- a/src/core-io/CMakeLists.txt
+++ b/src/core-io/CMakeLists.txt
@@ -22,9 +22,4 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(core-io
-    DEPENDENCIES
-        mp-units::core
-    HEADERS
-        include/units/quantity_io.h
-)
+add_units_module(core-io DEPENDENCIES mp-units::core HEADERS include/units/quantity_io.h)
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index cdc1eb36..431f258a 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -34,7 +34,9 @@ include(CheckLibcxxInUse)
 check_libcxx_in_use(${projectPrefix}LIBCXX)
 
 # core library definition
-add_library(mp-units-core INTERFACE
+add_library(
+    mp-units-core
+    INTERFACE
     include/units/base_dimension.h
     include/units/chrono.h
     include/units/concepts.h
diff --git a/src/systems/isq-iec80000/CMakeLists.txt b/src/systems/isq-iec80000/CMakeLists.txt
index 84e8f8d7..b2caa696 100644
--- a/src/systems/isq-iec80000/CMakeLists.txt
+++ b/src/systems/isq-iec80000/CMakeLists.txt
@@ -22,14 +22,10 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(isq-iec80000
-    DEPENDENCIES
-        mp-units::si
-    HEADERS
-        include/units/isq/iec80000/binary_prefixes.h
-        include/units/isq/iec80000/iec80000.h
-        include/units/isq/iec80000/modulation_rate.h
-        include/units/isq/iec80000/storage_capacity.h
-        include/units/isq/iec80000/traffic_intensity.h
-        include/units/isq/iec80000/transfer_rate.h
+add_units_module(
+    isq-iec80000
+    DEPENDENCIES mp-units::si
+    HEADERS include/units/isq/iec80000/binary_prefixes.h include/units/isq/iec80000/iec80000.h
+            include/units/isq/iec80000/modulation_rate.h include/units/isq/iec80000/storage_capacity.h
+            include/units/isq/iec80000/traffic_intensity.h include/units/isq/iec80000/transfer_rate.h
 )
diff --git a/src/systems/isq-natural/CMakeLists.txt b/src/systems/isq-natural/CMakeLists.txt
index b88038ce..e968bdff 100644
--- a/src/systems/isq-natural/CMakeLists.txt
+++ b/src/systems/isq-natural/CMakeLists.txt
@@ -22,19 +22,18 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(isq-natural
-    DEPENDENCIES
-        mp-units::isq
-    HEADERS
-        include/units/isq/natural/acceleration.h
-        include/units/isq/natural/constants.h
-        include/units/isq/natural/energy.h
-        include/units/isq/natural/force.h
-        include/units/isq/natural/length.h
-        include/units/isq/natural/mass.h
-        include/units/isq/natural/momentum.h
-        include/units/isq/natural/natural.h
-        include/units/isq/natural/speed.h
-        include/units/isq/natural/time.h
-        include/units/isq/natural/units.h
+add_units_module(
+    isq-natural
+    DEPENDENCIES mp-units::isq
+    HEADERS include/units/isq/natural/acceleration.h
+            include/units/isq/natural/constants.h
+            include/units/isq/natural/energy.h
+            include/units/isq/natural/force.h
+            include/units/isq/natural/length.h
+            include/units/isq/natural/mass.h
+            include/units/isq/natural/momentum.h
+            include/units/isq/natural/natural.h
+            include/units/isq/natural/speed.h
+            include/units/isq/natural/time.h
+            include/units/isq/natural/units.h
 )
diff --git a/src/systems/isq/CMakeLists.txt b/src/systems/isq/CMakeLists.txt
index 960a0114..c7dffcfc 100644
--- a/src/systems/isq/CMakeLists.txt
+++ b/src/systems/isq/CMakeLists.txt
@@ -22,53 +22,52 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(isq
-    DEPENDENCIES
-        mp-units::core
-    HEADERS
-        include/units/isq/dimensions/absorbed_dose.h
-        include/units/isq/dimensions/acceleration.h
-        include/units/isq/dimensions/amount_of_substance.h
-        include/units/isq/dimensions/angular_velocity.h
-        include/units/isq/dimensions/area.h
-        include/units/isq/dimensions/capacitance.h
-        include/units/isq/dimensions/catalytic_activity.h
-        include/units/isq/dimensions/charge_density.h
-        include/units/isq/dimensions/concentration.h
-        include/units/isq/dimensions/conductance.h
-        include/units/isq/dimensions/current_density.h
-        include/units/isq/dimensions/density.h
-        include/units/isq/dimensions/dynamic_viscosity.h
-        include/units/isq/dimensions/electric_charge.h
-        include/units/isq/dimensions/electric_current.h
-        include/units/isq/dimensions/electric_field_strength.h
-        include/units/isq/dimensions/energy.h
-        include/units/isq/dimensions/energy_density.h
-        include/units/isq/dimensions/force.h
-        include/units/isq/dimensions/frequency.h
-        include/units/isq/dimensions/heat_capacity.h
-        include/units/isq/dimensions/inductance.h
-        include/units/isq/dimensions/length.h
-        include/units/isq/dimensions/luminance.h
-        include/units/isq/dimensions/luminous_intensity.h
-        include/units/isq/dimensions/magnetic_flux.h
-        include/units/isq/dimensions/magnetic_induction.h
-        include/units/isq/dimensions/mass.h
-        include/units/isq/dimensions/molar_energy.h
-        include/units/isq/dimensions/momentum.h
-        include/units/isq/dimensions/permeability.h
-        include/units/isq/dimensions/permittivity.h
-        include/units/isq/dimensions/power.h
-        include/units/isq/dimensions/pressure.h
-        include/units/isq/dimensions/radioactivity.h
-        include/units/isq/dimensions/resistance.h
-        include/units/isq/dimensions/speed.h
-        include/units/isq/dimensions/surface_tension.h
-        include/units/isq/dimensions/thermal_conductivity.h
-        include/units/isq/dimensions/thermodynamic_temperature.h
-        include/units/isq/dimensions/time.h
-        include/units/isq/dimensions/torque.h
-        include/units/isq/dimensions/voltage.h
-        include/units/isq/dimensions/volume.h
-        include/units/isq/dimensions.h
+add_units_module(
+    isq
+    DEPENDENCIES mp-units::core
+    HEADERS include/units/isq/dimensions/absorbed_dose.h
+            include/units/isq/dimensions/acceleration.h
+            include/units/isq/dimensions/amount_of_substance.h
+            include/units/isq/dimensions/angular_velocity.h
+            include/units/isq/dimensions/area.h
+            include/units/isq/dimensions/capacitance.h
+            include/units/isq/dimensions/catalytic_activity.h
+            include/units/isq/dimensions/charge_density.h
+            include/units/isq/dimensions/concentration.h
+            include/units/isq/dimensions/conductance.h
+            include/units/isq/dimensions/current_density.h
+            include/units/isq/dimensions/density.h
+            include/units/isq/dimensions/dynamic_viscosity.h
+            include/units/isq/dimensions/electric_charge.h
+            include/units/isq/dimensions/electric_current.h
+            include/units/isq/dimensions/electric_field_strength.h
+            include/units/isq/dimensions/energy.h
+            include/units/isq/dimensions/energy_density.h
+            include/units/isq/dimensions/force.h
+            include/units/isq/dimensions/frequency.h
+            include/units/isq/dimensions/heat_capacity.h
+            include/units/isq/dimensions/inductance.h
+            include/units/isq/dimensions/length.h
+            include/units/isq/dimensions/luminance.h
+            include/units/isq/dimensions/luminous_intensity.h
+            include/units/isq/dimensions/magnetic_flux.h
+            include/units/isq/dimensions/magnetic_induction.h
+            include/units/isq/dimensions/mass.h
+            include/units/isq/dimensions/molar_energy.h
+            include/units/isq/dimensions/momentum.h
+            include/units/isq/dimensions/permeability.h
+            include/units/isq/dimensions/permittivity.h
+            include/units/isq/dimensions/power.h
+            include/units/isq/dimensions/pressure.h
+            include/units/isq/dimensions/radioactivity.h
+            include/units/isq/dimensions/resistance.h
+            include/units/isq/dimensions/speed.h
+            include/units/isq/dimensions/surface_tension.h
+            include/units/isq/dimensions/thermal_conductivity.h
+            include/units/isq/dimensions/thermodynamic_temperature.h
+            include/units/isq/dimensions/time.h
+            include/units/isq/dimensions/torque.h
+            include/units/isq/dimensions/voltage.h
+            include/units/isq/dimensions/volume.h
+            include/units/isq/dimensions.h
 )
diff --git a/src/systems/si-cgs/CMakeLists.txt b/src/systems/si-cgs/CMakeLists.txt
index 5a1cb20a..08316c20 100644
--- a/src/systems/si-cgs/CMakeLists.txt
+++ b/src/systems/si-cgs/CMakeLists.txt
@@ -22,19 +22,18 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-cgs
-    DEPENDENCIES
-        mp-units::si
-    HEADERS
-        include/units/isq/si/cgs/acceleration.h
-        include/units/isq/si/cgs/area.h
-        include/units/isq/si/cgs/cgs.h
-        include/units/isq/si/cgs/energy.h
-        include/units/isq/si/cgs/force.h
-        include/units/isq/si/cgs/length.h
-        include/units/isq/si/cgs/mass.h
-        include/units/isq/si/cgs/power.h
-        include/units/isq/si/cgs/pressure.h
-        include/units/isq/si/cgs/speed.h
-        include/units/isq/si/cgs/time.h
+add_units_module(
+    si-cgs
+    DEPENDENCIES mp-units::si
+    HEADERS include/units/isq/si/cgs/acceleration.h
+            include/units/isq/si/cgs/area.h
+            include/units/isq/si/cgs/cgs.h
+            include/units/isq/si/cgs/energy.h
+            include/units/isq/si/cgs/force.h
+            include/units/isq/si/cgs/length.h
+            include/units/isq/si/cgs/mass.h
+            include/units/isq/si/cgs/power.h
+            include/units/isq/si/cgs/pressure.h
+            include/units/isq/si/cgs/speed.h
+            include/units/isq/si/cgs/time.h
 )
diff --git a/src/systems/si-fps/CMakeLists.txt b/src/systems/si-fps/CMakeLists.txt
index 12f9bd9e..983a54db 100644
--- a/src/systems/si-fps/CMakeLists.txt
+++ b/src/systems/si-fps/CMakeLists.txt
@@ -22,22 +22,20 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-fps
-    DEPENDENCIES
-        mp-units::si
-    HEADERS
-        include/units/isq/si/fps/acceleration.h
-        include/units/isq/si/fps/area.h
-        include/units/isq/si/fps/density.h
-        include/units/isq/si/fps/energy.h
-        include/units/isq/si/fps/force.h
-        include/units/isq/si/fps/fps.h
-        include/units/isq/si/fps/length.h
-        include/units/isq/si/fps/mass.h
-        include/units/isq/si/fps/power.h
-        include/units/isq/si/fps/pressure.h
-        include/units/isq/si/fps/speed.h
-        include/units/isq/si/fps/time.h
-        include/units/isq/si/fps/volume.h
+add_units_module(
+    si-fps
+    DEPENDENCIES mp-units::si
+    HEADERS include/units/isq/si/fps/acceleration.h
+            include/units/isq/si/fps/area.h
+            include/units/isq/si/fps/density.h
+            include/units/isq/si/fps/energy.h
+            include/units/isq/si/fps/force.h
+            include/units/isq/si/fps/fps.h
+            include/units/isq/si/fps/length.h
+            include/units/isq/si/fps/mass.h
+            include/units/isq/si/fps/power.h
+            include/units/isq/si/fps/pressure.h
+            include/units/isq/si/fps/speed.h
+            include/units/isq/si/fps/time.h
+            include/units/isq/si/fps/volume.h
 )
-
diff --git a/src/systems/si-hep/CMakeLists.txt b/src/systems/si-hep/CMakeLists.txt
index 66747172..635d2981 100644
--- a/src/systems/si-hep/CMakeLists.txt
+++ b/src/systems/si-hep/CMakeLists.txt
@@ -22,13 +22,8 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-hep
-    DEPENDENCIES
-        mp-units::si
-    HEADERS
-        include/units/isq/si/hep/area.h
-        include/units/isq/si/hep/energy.h
-        include/units/isq/si/hep/hep.h
-        include/units/isq/si/hep/mass.h
-        include/units/isq/si/hep/momentum.h
+add_units_module(
+    si-hep DEPENDENCIES mp-units::si
+    HEADERS include/units/isq/si/hep/area.h include/units/isq/si/hep/energy.h include/units/isq/si/hep/hep.h
+            include/units/isq/si/hep/mass.h include/units/isq/si/hep/momentum.h
 )
diff --git a/src/systems/si-iau/CMakeLists.txt b/src/systems/si-iau/CMakeLists.txt
index 2677a344..7e86c0d2 100644
--- a/src/systems/si-iau/CMakeLists.txt
+++ b/src/systems/si-iau/CMakeLists.txt
@@ -22,10 +22,6 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-iau
-    DEPENDENCIES
-        mp-units::si
-    HEADERS
-        include/units/isq/si/iau/iau.h
-        include/units/isq/si/iau/length.h
+add_units_module(
+    si-iau DEPENDENCIES mp-units::si HEADERS include/units/isq/si/iau/iau.h include/units/isq/si/iau/length.h
 )
diff --git a/src/systems/si-imperial/CMakeLists.txt b/src/systems/si-imperial/CMakeLists.txt
index ac903b82..3a441611 100644
--- a/src/systems/si-imperial/CMakeLists.txt
+++ b/src/systems/si-imperial/CMakeLists.txt
@@ -22,10 +22,7 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-imperial
-    DEPENDENCIES
-        mp-units::si
-    HEADERS
-        include/units/isq/si/imperial/imperial.h
-        include/units/isq/si/imperial/length.h
+add_units_module(
+    si-imperial DEPENDENCIES mp-units::si HEADERS include/units/isq/si/imperial/imperial.h
+                                                  include/units/isq/si/imperial/length.h
 )
diff --git a/src/systems/si-international/CMakeLists.txt b/src/systems/si-international/CMakeLists.txt
index b62cd360..82c940fd 100644
--- a/src/systems/si-international/CMakeLists.txt
+++ b/src/systems/si-international/CMakeLists.txt
@@ -22,14 +22,10 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-international
-    DEPENDENCIES
-        mp-units::si
-    HEADERS
-        include/units/isq/si/international/area.h
-        include/units/isq/si/international/international.h
-        include/units/isq/si/international/length.h
-        include/units/isq/si/international/speed.h
-        include/units/isq/si/international/volume.h
+add_units_module(
+    si-international
+    DEPENDENCIES mp-units::si
+    HEADERS include/units/isq/si/international/area.h include/units/isq/si/international/international.h
+            include/units/isq/si/international/length.h include/units/isq/si/international/speed.h
+            include/units/isq/si/international/volume.h
 )
-
diff --git a/src/systems/si-typographic/CMakeLists.txt b/src/systems/si-typographic/CMakeLists.txt
index e8d17a84..7e359ea2 100644
--- a/src/systems/si-typographic/CMakeLists.txt
+++ b/src/systems/si-typographic/CMakeLists.txt
@@ -22,11 +22,7 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-typographic
-    DEPENDENCIES
-        mp-units::si
-    HEADERS
-        include/units/isq/si/typographic/length.h
-        include/units/isq/si/typographic/typographic.h
+add_units_module(
+    si-typographic DEPENDENCIES mp-units::si HEADERS include/units/isq/si/typographic/length.h
+                                                     include/units/isq/si/typographic/typographic.h
 )
-
diff --git a/src/systems/si-uscs/CMakeLists.txt b/src/systems/si-uscs/CMakeLists.txt
index 4bce00eb..1a10f79e 100644
--- a/src/systems/si-uscs/CMakeLists.txt
+++ b/src/systems/si-uscs/CMakeLists.txt
@@ -22,11 +22,6 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si-uscs
-    DEPENDENCIES
-        mp-units::si
-    HEADERS
-        include/units/isq/si/uscs/length.h
-        include/units/isq/si/uscs/uscs.h
+add_units_module(
+    si-uscs DEPENDENCIES mp-units::si HEADERS include/units/isq/si/uscs/length.h include/units/isq/si/uscs/uscs.h
 )
-
diff --git a/src/systems/si/CMakeLists.txt b/src/systems/si/CMakeLists.txt
index 5fd34835..f591c780 100644
--- a/src/systems/si/CMakeLists.txt
+++ b/src/systems/si/CMakeLists.txt
@@ -22,55 +22,54 @@
 
 cmake_minimum_required(VERSION 3.19)
 
-add_units_module(si
-    DEPENDENCIES
-        mp-units::isq
-    HEADERS
-        include/units/isq/si/absorbed_dose.h
-        include/units/isq/si/acceleration.h
-        include/units/isq/si/amount_of_substance.h
-        include/units/isq/si/angular_velocity.h
-        include/units/isq/si/area.h
-        include/units/isq/si/capacitance.h
-        include/units/isq/si/catalytic_activity.h
-        include/units/isq/si/charge_density.h
-        include/units/isq/si/concentration.h
-        include/units/isq/si/conductance.h
-        include/units/isq/si/constants.h
-        include/units/isq/si/current_density.h
-        include/units/isq/si/density.h
-        include/units/isq/si/dynamic_viscosity.h
-        include/units/isq/si/electric_charge.h
-        include/units/isq/si/electric_current.h
-        include/units/isq/si/electric_field_strength.h
-        include/units/isq/si/energy.h
-        include/units/isq/si/energy_density.h
-        include/units/isq/si/force.h
-        include/units/isq/si/frequency.h
-        include/units/isq/si/heat_capacity.h
-        include/units/isq/si/inductance.h
-        include/units/isq/si/length.h
-        include/units/isq/si/luminance.h
-        include/units/isq/si/luminous_intensity.h
-        include/units/isq/si/magnetic_flux.h
-        include/units/isq/si/magnetic_induction.h
-        include/units/isq/si/mass.h
-        include/units/isq/si/molar_energy.h
-        include/units/isq/si/momentum.h
-        include/units/isq/si/permeability.h
-        include/units/isq/si/permittivity.h
-        include/units/isq/si/power.h
-        include/units/isq/si/prefixes.h
-        include/units/isq/si/pressure.h
-        include/units/isq/si/radioactivity.h
-        include/units/isq/si/resistance.h
-        include/units/isq/si/si.h
-        include/units/isq/si/speed.h
-        include/units/isq/si/surface_tension.h
-        include/units/isq/si/thermal_conductivity.h
-        include/units/isq/si/thermodynamic_temperature.h
-        include/units/isq/si/time.h
-        include/units/isq/si/torque.h
-        include/units/isq/si/voltage.h
-        include/units/isq/si/volume.h
+add_units_module(
+    si
+    DEPENDENCIES mp-units::isq
+    HEADERS include/units/isq/si/absorbed_dose.h
+            include/units/isq/si/acceleration.h
+            include/units/isq/si/amount_of_substance.h
+            include/units/isq/si/angular_velocity.h
+            include/units/isq/si/area.h
+            include/units/isq/si/capacitance.h
+            include/units/isq/si/catalytic_activity.h
+            include/units/isq/si/charge_density.h
+            include/units/isq/si/concentration.h
+            include/units/isq/si/conductance.h
+            include/units/isq/si/constants.h
+            include/units/isq/si/current_density.h
+            include/units/isq/si/density.h
+            include/units/isq/si/dynamic_viscosity.h
+            include/units/isq/si/electric_charge.h
+            include/units/isq/si/electric_current.h
+            include/units/isq/si/electric_field_strength.h
+            include/units/isq/si/energy.h
+            include/units/isq/si/energy_density.h
+            include/units/isq/si/force.h
+            include/units/isq/si/frequency.h
+            include/units/isq/si/heat_capacity.h
+            include/units/isq/si/inductance.h
+            include/units/isq/si/length.h
+            include/units/isq/si/luminance.h
+            include/units/isq/si/luminous_intensity.h
+            include/units/isq/si/magnetic_flux.h
+            include/units/isq/si/magnetic_induction.h
+            include/units/isq/si/mass.h
+            include/units/isq/si/molar_energy.h
+            include/units/isq/si/momentum.h
+            include/units/isq/si/permeability.h
+            include/units/isq/si/permittivity.h
+            include/units/isq/si/power.h
+            include/units/isq/si/prefixes.h
+            include/units/isq/si/pressure.h
+            include/units/isq/si/radioactivity.h
+            include/units/isq/si/resistance.h
+            include/units/isq/si/si.h
+            include/units/isq/si/speed.h
+            include/units/isq/si/surface_tension.h
+            include/units/isq/si/thermal_conductivity.h
+            include/units/isq/si/thermodynamic_temperature.h
+            include/units/isq/si/time.h
+            include/units/isq/si/torque.h
+            include/units/isq/si/voltage.h
+            include/units/isq/si/volume.h
 )

From 74056fd6daa90a35959c54534c14554188f14148 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Sun, 24 Apr 2022 22:57:34 +0200
Subject: [PATCH 23/68] build: `clang-tidy` is not ready yet to be officially
 enabled in the project

---
 CMakeLists.txt | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index cbee492f..f0ca1045 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -57,13 +57,6 @@ if(${projectPrefix}IWYU)
     endif()
 endif()
 
-option(${projectPrefix}CLANG_TIDY "Enables clang-tidy" OFF)
-if(${projectPrefix}CLANG_TIDY)
-    message(STATUS "Enabling clang-tidy")
-    set(CMAKE_CXX_CLANG_TIDY clang-tidy)
-    message(STATUS "Enabling clang-tidy - done")
-endif()
-
 #enable_clang_tidy()
 
 # add project code

From 5d82969e0a2c7cd9faf0de7e4482839c40291494 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Tue, 26 Apr 2022 16:00:20 +0200
Subject: [PATCH 24/68] fix: enable SI prefixes for `Kelvin`

Resolves #359
---
 .../si/include/units/isq/si/thermodynamic_temperature.h        | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/systems/si/include/units/isq/si/thermodynamic_temperature.h b/src/systems/si/include/units/isq/si/thermodynamic_temperature.h
index 8989ca8d..04e81c35 100644
--- a/src/systems/si/include/units/isq/si/thermodynamic_temperature.h
+++ b/src/systems/si/include/units/isq/si/thermodynamic_temperature.h
@@ -29,11 +29,12 @@
 #include <units/symbol_text.h>
 // IWYU pragma: end_exports
 
+#include <units/isq/si/prefixes.h>
 #include <units/unit.h>
 
 namespace units::isq::si {
 
-struct kelvin : named_unit<kelvin, "K", no_prefix> {};
+struct kelvin : named_unit<kelvin, "K", prefix> {};
 
 struct dim_thermodynamic_temperature : isq::dim_thermodynamic_temperature<kelvin> {};
 

From 4361cb874e89776785be0149a2e17de1f0ef60aa Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 27 Apr 2022 19:32:21 +0200
Subject: [PATCH 25/68] fix: `hectare` definition fixed to be a prefixed
 version of `are` + other units

Relates to #359
---
 src/systems/si/include/units/isq/si/area.h | 42 +++++++++++++++++++++-
 test/unit_test/static/si_test.cpp          |  9 +++++
 2 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/src/systems/si/include/units/isq/si/area.h b/src/systems/si/include/units/isq/si/area.h
index 98bcb87c..a321fdda 100644
--- a/src/systems/si/include/units/isq/si/area.h
+++ b/src/systems/si/include/units/isq/si/area.h
@@ -58,7 +58,11 @@ struct square_exametre : derived_unit<square_exametre, dim_area, exametre> {};
 struct square_zettametre : derived_unit<square_zettametre, dim_area, zettametre> {};
 struct square_yottametre : derived_unit<square_yottametre, dim_area, yottametre> {};
 
-struct hectare : alias_unit<square_hectometre, "ha", no_prefix> {};
+struct are : alias_unit<square_decametre, "a", prefix> {};
+struct centiare : prefixed_alias_unit<square_metre, centi, are> {};
+struct deciare : prefixed_unit<deciare, deci, are> {};
+struct decare : prefixed_unit<decare, deca, are> {};
+struct hectare : prefixed_alias_unit<square_hectometre, hecto, are> {};
 
 template<UnitOf<dim_area> U, Representation Rep = double>
 using area = quantity<dim_area, U, Rep>;
@@ -235,6 +239,38 @@ constexpr auto operator"" _q_Ym2(unsigned long long l)
 }
 constexpr auto operator"" _q_Ym2(long double l) { return area<square_yottametre, long double>(l); }
 
+// a
+constexpr auto operator"" _q_a(unsigned long long l)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(l));
+  return area<are, std::int64_t>(static_cast<std::int64_t>(l));
+}
+constexpr auto operator"" _q_a(long double l) { return area<are, long double>(l); }
+
+// ca
+constexpr auto operator"" _q_ca(unsigned long long l)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(l));
+  return area<centiare, std::int64_t>(static_cast<std::int64_t>(l));
+}
+constexpr auto operator"" _q_ca(long double l) { return area<centiare, long double>(l); }
+
+// da
+constexpr auto operator"" _q_da(unsigned long long l)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(l));
+  return area<deciare, std::int64_t>(static_cast<std::int64_t>(l));
+}
+constexpr auto operator"" _q_da(long double l) { return area<deciare, long double>(l); }
+
+// daa
+constexpr auto operator"" _q_daa(unsigned long long l)
+{
+  gsl_ExpectsAudit(std::in_range<std::int64_t>(l));
+  return area<decare, std::int64_t>(static_cast<std::int64_t>(l));
+}
+constexpr auto operator"" _q_daa(long double l) { return area<decare, long double>(l); }
+
 // ha
 constexpr auto operator"" _q_ha(unsigned long long l)
 {
@@ -273,6 +309,10 @@ inline constexpr auto Em2 = reference<dim_area, square_exametre>{};
 inline constexpr auto Zm2 = reference<dim_area, square_zettametre>{};
 inline constexpr auto Ym2 = reference<dim_area, square_yottametre>{};
 
+inline constexpr auto a = reference<dim_area, are>{};
+inline constexpr auto ca = reference<dim_area, centiare>{};
+inline constexpr auto da = reference<dim_area, deciare>{};
+inline constexpr auto daa = reference<dim_area, decare>{};
 inline constexpr auto ha = reference<dim_area, hectare>{};
 
 }  // namespace area_references
diff --git a/test/unit_test/static/si_test.cpp b/test/unit_test/static/si_test.cpp
index a69c1f1b..5155f916 100644
--- a/test/unit_test/static/si_test.cpp
+++ b/test/unit_test/static/si_test.cpp
@@ -276,8 +276,17 @@ static_assert(10_q_m * 10_q_m == 100_q_m2);
 static_assert(100_q_m2 / 10_q_m == 10_q_m);
 static_assert(10_q_km * 10_q_km == 100_q_km2);
 static_assert(1_q_m2 == 10'000_q_cm2);
+
+static_assert(1_q_ca == 1_q_m2);
+static_assert(1_q_da == 10_q_m2);
+static_assert(1_q_a == 100_q_m2);
+static_assert(1_q_daa == 1'000_q_m2);
 static_assert(1_q_ha == 10'000_q_m2);
 
+static_assert(centiare::symbol == "ca");
+static_assert(deciare::symbol == "da");
+static_assert(are::symbol == "a");
+static_assert(decare::symbol == "daa");
 static_assert(hectare::symbol == "ha");
 
 static_assert(detail::unit_text<dim_area, square_metre>() == basic_symbol_text("m²", "m^2"));

From fbc6744bdbabb8e32e4d115474f9c7a6a499f579 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 27 Apr 2022 19:33:44 +0200
Subject: [PATCH 26/68] =?UTF-8?q?fix:=20`=CF=89`,=20`au`,=20and=20`Da`=20a?=
 =?UTF-8?q?llowed=20to=20have=20SI=20prefixes?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Relates to #359
---
 src/systems/si/include/units/isq/si/angular_velocity.h | 3 ++-
 src/systems/si/include/units/isq/si/length.h           | 2 +-
 src/systems/si/include/units/isq/si/mass.h             | 2 +-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/systems/si/include/units/isq/si/angular_velocity.h b/src/systems/si/include/units/isq/si/angular_velocity.h
index fbb6e5c6..0cbcf686 100644
--- a/src/systems/si/include/units/isq/si/angular_velocity.h
+++ b/src/systems/si/include/units/isq/si/angular_velocity.h
@@ -29,12 +29,13 @@
 // IWYU pragma: end_exports
 
 #include <units/generic/angle.h>
+#include <units/isq/si/prefixes.h>
 #include <units/isq/si/time.h>
 #include <units/unit.h>
 
 namespace units::isq::si {
 
-struct radian_per_second : named_unit<radian_per_second, basic_symbol_text{"ω", "w"}, no_prefix> {};
+struct radian_per_second : named_unit<radian_per_second, basic_symbol_text{"ω", "w"}, prefix> {};
 
 struct dim_angular_velocity :
     isq::dim_angular_velocity<dim_angular_velocity, radian_per_second, dim_angle<>, dim_time> {};
diff --git a/src/systems/si/include/units/isq/si/length.h b/src/systems/si/include/units/isq/si/length.h
index eee2c9d2..36022dbd 100644
--- a/src/systems/si/include/units/isq/si/length.h
+++ b/src/systems/si/include/units/isq/si/length.h
@@ -56,7 +56,7 @@ struct exametre : prefixed_unit<exametre, exa, metre> {};
 struct zettametre : prefixed_unit<zettametre, zetta, metre> {};
 struct yottametre : prefixed_unit<yottametre, yotta, metre> {};
 
-struct astronomical_unit : named_scaled_unit<astronomical_unit, "au", no_prefix, ratio(149'597'870'700), metre> {};
+struct astronomical_unit : named_scaled_unit<astronomical_unit, "au", prefix, ratio(149'597'870'700), metre> {};
 
 struct dim_length : isq::dim_length<metre> {};
 
diff --git a/src/systems/si/include/units/isq/si/mass.h b/src/systems/si/include/units/isq/si/mass.h
index 620381b3..89776694 100644
--- a/src/systems/si/include/units/isq/si/mass.h
+++ b/src/systems/si/include/units/isq/si/mass.h
@@ -79,7 +79,7 @@ struct zettatonne : prefixed_unit<zettatonne, zetta, tonne> {};
 struct yottatonne : prefixed_unit<yottatonne, yotta, tonne> {};
 
 struct dalton :
-    named_scaled_unit<dalton, "Da", no_prefix, ratio(16'605'390'666'050, 10'000'000'000'000, -27), kilogram> {};
+    named_scaled_unit<dalton, "Da", prefix, ratio(16'605'390'666'050, 10'000'000'000'000, -27), kilogram> {};
 
 struct dim_mass : isq::dim_mass<kilogram> {};
 

From 6d6bf81003ef707e1c7b56bff27aebc921f395a8 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 5 May 2022 09:46:35 +0200
Subject: [PATCH 27/68] build(conan): Upgrading the recipe to Conan 2.0

---
 conanfile.py | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/conanfile.py b/conanfile.py
index 98add025..7a5b57f4 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -20,14 +20,14 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-from conans import ConanFile, tools
-from conans.tools import Version, check_min_cppstd
+from conan import ConanFile
 from conan.tools.cmake import CMakeToolchain, CMakeDeps, CMake
-from conan.tools.files import copy
-from conans.errors import ConanInvalidConfiguration
+from conan.tools.files import copy, load, rmdir
+from conan.tools.scm import Version
+from conans.tools import get_env, check_min_cppstd   # TODO replace with new tools for Conan 2.0
 import os, re
 
-required_conan_version = ">=1.44.0"
+required_conan_version = ">=1.48.0"
 
 
 class MPUnitsConan(ConanFile):
@@ -67,7 +67,7 @@ class MPUnitsConan(ConanFile):
 
     @property
     def _run_tests(self):
-        return tools.get_env("CONAN_RUN_TESTS", False)
+        return get_env("CONAN_RUN_TESTS", False)
 
     @property
     def _use_libfmt(self):
@@ -93,7 +93,7 @@ class MPUnitsConan(ConanFile):
             return int(f"{compiler.version}0")
 
     def set_version(self):
-        content = tools.load(os.path.join(self.recipe_folder, "src/CMakeLists.txt"))
+        content = load(self, os.path.join(self.recipe_folder, "src/CMakeLists.txt"))
         version = re.search(r"project\([^\)]+VERSION (\d+\.\d+\.\d+)[^\)]*\)", content).group(1)
         self.version = version.strip()
 
@@ -164,7 +164,7 @@ class MPUnitsConan(ConanFile):
         copy(self, "LICENSE.md", self.source_folder, os.path.join(self.package_folder, "licenses"))
         cmake = CMake(self)
         cmake.install()
-        tools.rmdir(os.path.join(self.package_folder, "lib", "cmake"))
+        rmdir(self, os.path.join(self.package_folder, "lib", "cmake"))
 
     def package_info(self):
         compiler = self.settings.compiler

From 4adc71db56ed557996fe473f981ee6a7845451aa Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 5 May 2022 11:53:37 +0200
Subject: [PATCH 28/68] build(conan): `exports_sources` replaced with the
 `scm.Git`

---
 conanfile.py | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/conanfile.py b/conanfile.py
index 7a5b57f4..874852b9 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -22,8 +22,8 @@
 
 from conan import ConanFile
 from conan.tools.cmake import CMakeToolchain, CMakeDeps, CMake
-from conan.tools.files import copy, load, rmdir
-from conan.tools.scm import Version
+from conan.tools.files import copy, load, rmdir, update_conandata
+from conan.tools.scm import Git, Version
 from conans.tools import get_env, check_min_cppstd   # TODO replace with new tools for Conan 2.0
 import os, re
 
@@ -62,7 +62,6 @@ class MPUnitsConan(ConanFile):
         "build_docs": True
     }
     exports = ["LICENSE.md"]
-    exports_sources = ["docs/*", "src/*", "test/*", "cmake/*", "example/*", "CMakeLists.txt"]
     generators = "cmake_paths"
 
     @property
@@ -140,6 +139,22 @@ class MPUnitsConan(ConanFile):
     #         # build_docs has sense only in a development or CI build
     #         del self.options.build_docs
 
+    def export(self):
+        git = Git(self, self.recipe_folder)
+        scm_url, scm_commit = git.get_url_and_commit()
+        # stores the current url and commit in conandata.yml
+        update_conandata(self, {"sources": {"commit": scm_commit, "url": scm_url}})
+
+    def layout(self):
+        self.folders.source = "."
+
+    def source(self):
+        # recovers the saved url and commit from conandata.yml and use them to get sources
+        git = Git(self)
+        sources = self.conan_data["sources"]
+        git.clone(url=sources["url"], target=".")
+        git.checkout(commit=sources["commit"])
+
     def generate(self):
         tc = CMakeToolchain(self)
         tc.variables["UNITS_DOWNCAST_MODE"] = str(self.options.downcast_mode).upper()

From 640fa670f874fb8077423b535e29af2762675794 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 5 May 2022 11:54:23 +0200
Subject: [PATCH 29/68] build(conan): `no_copy_source` attribute added

---
 conanfile.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/conanfile.py b/conanfile.py
index 874852b9..c88ec456 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -62,6 +62,7 @@ class MPUnitsConan(ConanFile):
         "build_docs": True
     }
     exports = ["LICENSE.md"]
+    no_copy_source = True
     generators = "cmake_paths"
 
     @property

From 0033319451f0dc812364ef96b288f2c99f45c770 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 5 May 2022 16:12:54 +0200
Subject: [PATCH 30/68] fix: shadowing compilation errors on MSVC fixed

---
 src/core/include/units/symbol_text.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/core/include/units/symbol_text.h b/src/core/include/units/symbol_text.h
index 3af267a0..adf138e5 100644
--- a/src/core/include/units/symbol_text.h
+++ b/src/core/include/units/symbol_text.h
@@ -78,16 +78,16 @@ struct basic_symbol_text {
   {
     detail::validate_ascii_string<N>(std.data_);
   }
-  constexpr basic_symbol_text(const StandardCharT (&std)[N + 1], const char (&a)[M + 1]) noexcept :
-      standard_(std), ascii_(a)
+  constexpr basic_symbol_text(const StandardCharT (&std)[N + 1], const char (&ascii)[M + 1]) noexcept :
+      standard_(std), ascii_(ascii)
   {
-    detail::validate_ascii_string<M>(a);
+    detail::validate_ascii_string<M>(ascii);
   }
   constexpr basic_symbol_text(const basic_fixed_string<StandardCharT, N>& std,
-                              const basic_fixed_string<char, M>& a) noexcept :
-      standard_(std), ascii_(a)
+                              const basic_fixed_string<char, M>& ascii) noexcept :
+      standard_(std), ascii_(ascii)
   {
-    detail::validate_ascii_string<M>(a.data_);
+    detail::validate_ascii_string<M>(ascii.data_);
   }
 
   [[nodiscard]] constexpr auto& standard() { return standard_; }

From fde503202591a1cc03704b5ad73e926514269772 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 5 May 2022 19:18:19 +0200
Subject: [PATCH 31/68] Revert "build(conan): `exports_sources` replaced with
 the `scm.Git`"

This reverts commit 4adc71db56ed557996fe473f981ee6a7845451aa.
---
 conanfile.py | 21 +++------------------
 1 file changed, 3 insertions(+), 18 deletions(-)

diff --git a/conanfile.py b/conanfile.py
index c88ec456..6eeb8e75 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -22,8 +22,8 @@
 
 from conan import ConanFile
 from conan.tools.cmake import CMakeToolchain, CMakeDeps, CMake
-from conan.tools.files import copy, load, rmdir, update_conandata
-from conan.tools.scm import Git, Version
+from conan.tools.files import copy, load, rmdir
+from conan.tools.scm import Version
 from conans.tools import get_env, check_min_cppstd   # TODO replace with new tools for Conan 2.0
 import os, re
 
@@ -62,6 +62,7 @@ class MPUnitsConan(ConanFile):
         "build_docs": True
     }
     exports = ["LICENSE.md"]
+    exports_sources = ["docs/*", "src/*", "test/*", "cmake/*", "example/*", "CMakeLists.txt"]
     no_copy_source = True
     generators = "cmake_paths"
 
@@ -140,22 +141,6 @@ class MPUnitsConan(ConanFile):
     #         # build_docs has sense only in a development or CI build
     #         del self.options.build_docs
 
-    def export(self):
-        git = Git(self, self.recipe_folder)
-        scm_url, scm_commit = git.get_url_and_commit()
-        # stores the current url and commit in conandata.yml
-        update_conandata(self, {"sources": {"commit": scm_commit, "url": scm_url}})
-
-    def layout(self):
-        self.folders.source = "."
-
-    def source(self):
-        # recovers the saved url and commit from conandata.yml and use them to get sources
-        git = Git(self)
-        sources = self.conan_data["sources"]
-        git.clone(url=sources["url"], target=".")
-        git.checkout(commit=sources["commit"])
-
     def generate(self):
         tc = CMakeToolchain(self)
         tc.variables["UNITS_DOWNCAST_MODE"] = str(self.options.downcast_mode).upper()

From ffa0f321f957f79f4bd7d3b237abd1f40e9b4ec0 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 6 May 2022 10:00:39 +0200
Subject: [PATCH 32/68] fix: shadowing compilation errors on MSVC fixed

---
 test/unit_test/static/quantity_test.cpp | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/test/unit_test/static/quantity_test.cpp b/test/unit_test/static/quantity_test.cpp
index 0f810ccf..fff7d9e4 100644
--- a/test/unit_test/static/quantity_test.cpp
+++ b/test/unit_test/static/quantity_test.cpp
@@ -275,11 +275,11 @@ struct derived_quantity : quantity<typename Q::dimension, typename Q::unit, Rep>
 static_assert(detail::is_quantity<derived_quantity<double, si::length<metre>, "NTTP type description">>);
 constexpr isq::Length auto get_length_derived_quantity() noexcept
 {
-  derived_quantity<double, si::length<metre>, "NTTP type description"> a{};
-  a += 1_q_m;
-  a = a + 1_q_m;
-  a *= 0.5;
-  return a;
+  derived_quantity<double, si::length<metre>, "NTTP type description"> dist{};
+  dist += 1_q_m;
+  dist = dist + 1_q_m;
+  dist *= 0.5;
+  return dist;
 }
 static_assert(get_length_derived_quantity() == 1_q_m);
 

From ba0e1c52b5d0d011461ec495259dd6cca847e5d2 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 6 May 2022 18:30:20 +0200
Subject: [PATCH 33/68] style: `ci-test-package-cmake.yml` reformatted

---
 .github/workflows/ci-test-package-cmake.yml | 105 +++++++++++---------
 1 file changed, 57 insertions(+), 48 deletions(-)

diff --git a/.github/workflows/ci-test-package-cmake.yml b/.github/workflows/ci-test-package-cmake.yml
index 568083a7..68f02bd1 100644
--- a/.github/workflows/ci-test-package-cmake.yml
+++ b/.github/workflows/ci-test-package-cmake.yml
@@ -25,14 +25,14 @@ name: CMake Test Package CI
 on:
   push:
     paths-ignore:
-    - 'docs/**'
-    - 'example/**'
-    - 'test/**'
+      - "docs/**"
+      - "example/**"
+      - "test/**"
   pull_request:
     paths-ignore:
-    - 'docs/**'
-    - 'example/**'
-    - 'test/**'
+      - "docs/**"
+      - "example/**"
+      - "test/**"
 
 jobs:
   test_package:
@@ -42,46 +42,55 @@ jobs:
       fail-fast: false
       matrix:
         config:
-        - {
-            name: "Windows MSVC 2019",
-            os: windows-latest,
-            compiler: { type: VISUAL, version: 16, cc: "", cxx: "" }
-          }
-        - {
-            name: "Ubuntu GCC 10.3.0",
-            os: ubuntu-20.04,
-            compiler: { type: GCC, version: 10, cc: "gcc-10", cxx: "g++-10" },
-            lib: "libstdc++11"
-          }
-        - {
-            name: "Ubuntu GCC 11.1.0",
-            os: ubuntu-20.04,
-            compiler: { type: GCC, version: 11, cc: "gcc-11", cxx: "g++-11" },
-            lib: "libstdc++11"
-          }
-        - {
-            name: "Ubuntu Clang 12.0.0 + libstdc++11",
-            os: ubuntu-20.04,
-            compiler: { type: CLANG, version: 12, cc: "clang-12", cxx: "clang++-12" },
-            lib: "libstdc++11"
-          }
-        - {
-            name: "Ubuntu Clang 12.0.0 + libc++",
-            os: ubuntu-20.04,
-            compiler: { type: CLANG, version: 12, cc: "clang-12", cxx: "clang++-12" },
-            lib: "libc++"
-          }
-        - {
-            name: "Ubuntu Clang 13.0.0 + libc++",
-            os: ubuntu-20.04,
-            compiler: { type: CLANG, version: 13, cc: "clang-13", cxx: "clang++-13" },
-            lib: "libc++"
-          }
-        - {
-            name: "MacOS Apple Clang 13",
-            os: macos-11,
-            compiler: { type: APPLE_CLANG, version: "13.0", cc: "clang", cxx: "clang++" }
-          }
+          - {
+              name: "Windows MSVC 2019",
+              os: windows-latest,
+              compiler: { type: VISUAL, version: 16, cc: "", cxx: "" },
+            }
+          - {
+              name: "Ubuntu GCC 10.3.0",
+              os: ubuntu-20.04,
+              compiler: { type: GCC, version: 10, cc: "gcc-10", cxx: "g++-10" },
+              lib: "libstdc++11",
+            }
+          - {
+              name: "Ubuntu GCC 11.1.0",
+              os: ubuntu-20.04,
+              compiler: { type: GCC, version: 11, cc: "gcc-11", cxx: "g++-11" },
+              lib: "libstdc++11",
+            }
+          - {
+              name: "Ubuntu Clang 12.0.0 + libstdc++11",
+              os: ubuntu-20.04,
+              compiler:
+                { type: CLANG, version: 12, cc: "clang-12", cxx: "clang++-12" },
+              lib: "libstdc++11",
+            }
+          - {
+              name: "Ubuntu Clang 12.0.0 + libc++",
+              os: ubuntu-20.04,
+              compiler:
+                { type: CLANG, version: 12, cc: "clang-12", cxx: "clang++-12" },
+              lib: "libc++",
+            }
+          - {
+              name: "Ubuntu Clang 13.0.0 + libc++",
+              os: ubuntu-20.04,
+              compiler:
+                { type: CLANG, version: 13, cc: "clang-13", cxx: "clang++-13" },
+              lib: "libc++",
+            }
+          - {
+              name: "MacOS Apple Clang 13",
+              os: macos-11,
+              compiler:
+                {
+                  type: APPLE_CLANG,
+                  version: "13.0",
+                  cc: "clang",
+                  cxx: "clang++",
+                },
+            }
         # In case a Conan docker image will be needed to provide a specific configuration we can use a Docker image as follows
         # - {
         #     name: "Ubuntu GCC 10.2.0",
@@ -89,7 +98,7 @@ jobs:
         #     compiler: { type: GCC, version: 10, cc: "gcc-10", cxx: "g++-10" },
         #     docker_image: conanio/gcc10
         #   }
-        build_type: [ "Release", "Debug" ]
+        build_type: ["Release", "Debug"]
 
     env:
       CC: ${{ matrix.config.compiler.cc }}
@@ -151,7 +160,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v2
         with:
-          python-version: '3.8'
+          python-version: "3.8"
       - name: Install Conan
         shell: bash
         run: |

From f8837de0cb2a200fa13e09b2177f52891fe5bf5a Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 6 May 2022 18:36:27 +0200
Subject: [PATCH 34/68] ci: Conan 1.48 does not set `CMAKE_BUILD_TYPE` in the
 `conan_toolchain.cmake` anymore

---
 .github/workflows/ci-test-package-cmake.yml | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/.github/workflows/ci-test-package-cmake.yml b/.github/workflows/ci-test-package-cmake.yml
index 68f02bd1..2337af7e 100644
--- a/.github/workflows/ci-test-package-cmake.yml
+++ b/.github/workflows/ci-test-package-cmake.yml
@@ -194,13 +194,13 @@ jobs:
         working-directory: build/${{ matrix.build_type }}
         run: |
           call conanvcvars.bat
-          cmake ../../src -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake
+          cmake ../../src -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}
       - name: Configure mp-units CMake
         if: matrix.config.compiler.type != 'VISUAL'
         shell: bash
         working-directory: build/${{ matrix.build_type }}
         run: |
-          cmake ../../src -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake
+          cmake ../../src -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}
       - name: Install mp-units
         shell: bash
         working-directory: build/${{ matrix.build_type }}
@@ -217,14 +217,14 @@ jobs:
         working-directory: test_package/build/${{ matrix.build_type }}
         run: |
           call conanvcvars.bat
-          cmake ../.. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -Dmp-units_DIR=${{ github.workspace }}/build/${{ matrix.build_type }}
+          cmake ../.. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=${{ matrix.build_type }} -Dmp-units_DIR=${{ github.workspace }}/build/${{ matrix.build_type }}
           cmake --build .
       - name: Build test_package CMake (local build)
         if: matrix.config.compiler.type != 'VISUAL'
         shell: bash
         working-directory: test_package/build/${{ matrix.build_type }}
         run: |
-          cmake ../.. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -Dmp-units_DIR=${{ github.workspace }}/build/${{ matrix.build_type }}
+          cmake ../.. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=${{ matrix.build_type }} -Dmp-units_DIR=${{ github.workspace }}/build/${{ matrix.build_type }}
           cmake --build .
       - name: Build test_package CMake (installation)
         if: matrix.config.compiler.type == 'VISUAL'
@@ -232,14 +232,14 @@ jobs:
         working-directory: test_package/build/${{ matrix.build_type }}
         run: |
           call conanvcvars.bat
-          cmake ../.. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_INSTALL_PREFIX=../../../build/${{ matrix.build_type }}/test_package
+          cmake ../.. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=${{ matrix.build_type }} -DCMAKE_INSTALL_PREFIX=../../../build/${{ matrix.build_type }}/test_package
           cmake --build .
       - name: Build test_package CMake (installation)
         if: matrix.config.compiler.type != 'VISUAL'
         shell: bash
         working-directory: test_package/build/${{ matrix.build_type }}
         run: |
-          cmake ../.. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_INSTALL_PREFIX=../../../build/${{ matrix.build_type }}/test_package
+          cmake ../.. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=${{ matrix.build_type }} -DCMAKE_INSTALL_PREFIX=../../../build/${{ matrix.build_type }}/test_package
           cmake --build .
       - name: Run test_package
         shell: bash

From 75ca6f1aefc8c9be6e5f51dd1851e01500345daf Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 6 May 2022 18:40:03 +0200
Subject: [PATCH 35/68] docs: Conan 1.48 does not set `CMAKE_BUILD_TYPE` in the
 `conan_toolchain.cmake` anymore

---
 docs/usage.rst | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/docs/usage.rst b/docs/usage.rst
index bc289de5..bde4ea77 100644
--- a/docs/usage.rst
+++ b/docs/usage.rst
@@ -294,7 +294,7 @@ library release the following steps may be performed:
 
       mkdir my_project/build && cd my_project/build
       conan install .. -pr <your_conan_profile> -s compiler.cppstd=20 -b=missing
-      cmake .. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake
+      cmake .. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=Release
       cmake --build .
 
 
@@ -345,7 +345,7 @@ differences:
 
       mkdir my_project/build && cd my_project/build
       conan install .. -pr <your_conan_profile> -s compiler.cppstd=20 -b=outdated -u
-      cmake .. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake
+      cmake .. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=Release
       cmake --build .
 
 
@@ -360,7 +360,7 @@ to find it, it is enough to perform the following steps:
 
     mkdir units/build && cd units/build
     conan install .. -pr <your_conan_profile> -s compiler.cppstd=20 -b=missing
-    cmake ../src -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake
+    cmake ../src -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=Release
     cmake --install . --prefix <install_dir>
 
 
@@ -392,7 +392,7 @@ step with the CMake build:
 .. code-block:: shell
 
     # ...
-    cmake .. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake
+    cmake .. -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake -DCMAKE_BUILD_TYPE=Release
     cmake --build .
     ctest
 

From 8507ed1ae94ffd457c5973ad7d7baeb03cdad54e Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Mon, 9 May 2022 12:24:50 +0200
Subject: [PATCH 36/68] chore: `CMakeUserPresets.json` file should not be added
 to the repo

---
 .gitignore | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/.gitignore b/.gitignore
index 751b2745..a4547914 100644
--- a/.gitignore
+++ b/.gitignore
@@ -40,6 +40,9 @@
 /out/
 _build/
 
+# CMake
+CMakeUserPresets.json
+
 # Conan
 *.pyc
 /test_package/build/

From a7f1817c9bbb12c6e6c6401c77ad9d07f0684b0d Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Mon, 9 May 2022 13:59:56 +0200
Subject: [PATCH 37/68] feat: SI prefixes allowed for a `yard` unit as at least
 `kiloyard` is used in some domains

---
 .../include/units/isq/si/international/length.h                 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/systems/si-international/include/units/isq/si/international/length.h b/src/systems/si-international/include/units/isq/si/international/length.h
index e37944a0..ead14a46 100644
--- a/src/systems/si-international/include/units/isq/si/international/length.h
+++ b/src/systems/si-international/include/units/isq/si/international/length.h
@@ -37,7 +37,7 @@ namespace units::isq::si::international {
 
 // si::international yard
 // https://en.wikipedia.org/wiki/International_yard_and_pound
-struct yard : named_scaled_unit<yard, "yd", no_prefix, ratio(9'144, 1'000, -1), si::metre> {};
+struct yard : named_scaled_unit<yard, "yd", si::prefix, ratio(9'144, 1'000, -1), si::metre> {};
 
 // si::international foot
 // https://en.wikipedia.org/wiki/Foot_(unit)#International_foot

From 8b52f46bed969abf8de3980f849b61e4a0d9d66d Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Mon, 9 May 2022 14:01:08 +0200
Subject: [PATCH 38/68] fix: `fps` can now coexist with `international` system

Resolves #347
---
 src/systems/si-fps/CMakeLists.txt             |  2 +-
 .../si-fps/include/units/isq/si/fps/length.h  | 19 ++++++++-----------
 2 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/src/systems/si-fps/CMakeLists.txt b/src/systems/si-fps/CMakeLists.txt
index 983a54db..ffd302de 100644
--- a/src/systems/si-fps/CMakeLists.txt
+++ b/src/systems/si-fps/CMakeLists.txt
@@ -24,7 +24,7 @@ cmake_minimum_required(VERSION 3.19)
 
 add_units_module(
     si-fps
-    DEPENDENCIES mp-units::si
+    DEPENDENCIES mp-units::si-international
     HEADERS include/units/isq/si/fps/acceleration.h
             include/units/isq/si/fps/area.h
             include/units/isq/si/fps/density.h
diff --git a/src/systems/si-fps/include/units/isq/si/fps/length.h b/src/systems/si-fps/include/units/isq/si/fps/length.h
index a4307180..c33819cd 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/length.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/length.h
@@ -29,24 +29,21 @@
 #include <units/symbol_text.h>
 // IWYU pragma: end_exports
 
-#include <units/isq/si/length.h>
+#include <units/isq/si/international/length.h>
 #include <units/unit.h>
 
 namespace units::isq::si::fps {
 
 // https://en.wikipedia.org/wiki/Foot_(unit)
-struct foot : named_scaled_unit<foot, "ft", no_prefix, ratio(3'048, 1'000, -1), si::metre> {};
-
-struct inch : named_scaled_unit<inch, "in", no_prefix, ratio(1, 12), foot> {};
+using si::international::fathom;
+using si::international::foot;
+using si::international::inch;
+using si::international::mil;
+using si::international::thou;
+using si::international::yard;
 
 // thousandth of an inch
-struct thousandth : named_scaled_unit<thousandth, "thou", no_prefix, ratio(1, 1'000), inch> {};
-struct thou : alias_unit<thousandth, "thou", no_prefix> {};
-struct mil : alias_unit<thousandth, "mil", no_prefix> {};
-
-struct yard : named_scaled_unit<yard, "yd", si::prefix, ratio(3, 1), foot> {};
-
-struct fathom : named_scaled_unit<fathom, "ftm", no_prefix, ratio(6, 1), foot> {};
+struct thousandth : alias_unit<thou, "thou", no_prefix> {};
 
 struct kiloyard : prefixed_unit<kiloyard, si::kilo, yard> {};
 

From 0b8e5c0dfe5b792fa94acd0cce69c965c961ad5a Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Mon, 9 May 2022 14:03:14 +0200
Subject: [PATCH 39/68] fix(example): `foot_pound_second` example now correctly
 uses `international::knot` which is typical for Marine industry

Resolves #357
---
 example/aliases/foot_pound_second.cpp    |  7 ++++---
 example/literals/foot_pound_second.cpp   | 10 ++++++----
 example/references/foot_pound_second.cpp | 10 ++++++----
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/example/aliases/foot_pound_second.cpp b/example/aliases/foot_pound_second.cpp
index 12b1082d..8890a92f 100644
--- a/example/aliases/foot_pound_second.cpp
+++ b/example/aliases/foot_pound_second.cpp
@@ -26,6 +26,7 @@
 #include <units/isq/si/fps/mass.h>
 #include <units/isq/si/fps/power.h>
 #include <units/isq/si/fps/speed.h>
+#include <units/isq/si/international/speed.h>
 #include <units/isq/si/length.h>
 #include <units/isq/si/mass.h>
 #include <units/isq/si/power.h>
@@ -68,7 +69,7 @@ void print_details(std::string_view description, const Ship& ship)
             << STD_FMT::format("{:20} : {}\n", "beam", fmt_line<si::fps::length::yd<>, si::length::m<>>(ship.beam))
             << STD_FMT::format("{:20} : {}\n", "mass", fmt_line<si::fps::mass::lton<>, si::mass::t<>>(ship.mass))
             << STD_FMT::format("{:20} : {}\n", "speed",
-                               fmt_line<si::fps::speed::kn<>, si::speed::km_per_h<>>(ship.speed))
+                               fmt_line<si::international::speed::kn<>, si::speed::km_per_h<>>(ship.speed))
             << STD_FMT::format("{:20} : {}\n", "power", fmt_line<si::fps::power::hp<>, si::power::kW<>>(ship.power))
             << STD_FMT::format("{:20} : {}\n", "main guns",
                                fmt_line<si::fps::length::in<>, si::length::mm<>>(ship.mainGuns))
@@ -101,7 +102,7 @@ int main()
   auto iowa = Ship{.length{ft<>(860.)},
                    .draft{ft<>(37.) + in<>(2.)},
                    .beam{ft<>(108.) + in<>(2.)},
-                   .speed{kn<>(33)},
+                   .speed{international::kn<>(33)},
                    .mass{lton<>(57'540)},
                    .mainGuns{in<>(16)},
                    .shellMass{lb<>(2700)},
@@ -112,7 +113,7 @@ int main()
   auto kgv = Ship{.length{ft<>(745.1)},
                   .draft{ft<>(33.) + in<>(7.5)},
                   .beam{ft<>(103.2) + in<>(2.5)},
-                  .speed{kn<>(28.3)},
+                  .speed{international::kn<>(28.3)},
                   .mass{lton<>(42'245)},
                   .mainGuns{in<>(14)},
                   .shellMass{lb<>(1'590)},
diff --git a/example/literals/foot_pound_second.cpp b/example/literals/foot_pound_second.cpp
index 67d1d296..01f8d285 100644
--- a/example/literals/foot_pound_second.cpp
+++ b/example/literals/foot_pound_second.cpp
@@ -26,6 +26,7 @@
 #include <units/isq/si/fps/mass.h>
 #include <units/isq/si/fps/power.h>
 #include <units/isq/si/fps/speed.h>
+#include <units/isq/si/international/speed.h>
 #include <units/isq/si/length.h>
 #include <units/isq/si/mass.h>
 #include <units/isq/si/power.h>
@@ -73,8 +74,9 @@ void print_details(std::string_view description, const Ship& ship)
                                fmt_line<si::fps::length<si::fps::yard>, si::length<si::metre>>(ship.beam))
             << STD_FMT::format("{:20} : {}\n", "mass",
                                fmt_line<si::fps::mass<si::fps::long_ton>, si::mass<si::tonne>>(ship.mass))
-            << STD_FMT::format("{:20} : {}\n", "speed",
-                               fmt_line<si::fps::speed<si::fps::knot>, si::speed<si::kilometre_per_hour>>(ship.speed))
+            << STD_FMT::format(
+                 "{:20} : {}\n", "speed",
+                 fmt_line<si::speed<si::international::knot>, si::speed<si::kilometre_per_hour>>(ship.speed))
             << STD_FMT::format("{:20} : {}\n", "power",
                                fmt_line<si::fps::power<si::fps::horse_power>, si::power<si::kilowatt>>(ship.power))
             << STD_FMT::format("{:20} : {}\n", "main guns",
@@ -108,7 +110,7 @@ int main()
   auto iowa = Ship{.length{860._q_ft},
                    .draft{37._q_ft + 2._q_in},
                    .beam{108._q_ft + 2._q_in},
-                   .speed{33_q_kn},
+                   .speed{si::speed<si::international::knot>{33}},
                    .mass{57'540_q_lton},
                    .mainGuns{16_q_in},
                    .shellMass{2700_q_lb},
@@ -119,7 +121,7 @@ int main()
   auto kgv = Ship{.length{745.1_q_ft},
                   .draft{33._q_ft + 7.5_q_in},
                   .beam{103.2_q_ft + 2.5_q_in},
-                  .speed{28.3_q_kn},
+                  .speed{si::speed<si::international::knot>{28.3}},
                   .mass{42'245_q_lton},
                   .mainGuns{14_q_in},
                   .shellMass{1'590_q_lb},
diff --git a/example/references/foot_pound_second.cpp b/example/references/foot_pound_second.cpp
index ca1f5447..0833fa6b 100644
--- a/example/references/foot_pound_second.cpp
+++ b/example/references/foot_pound_second.cpp
@@ -28,6 +28,7 @@
 #include <units/isq/si/fps/speed.h>
 #include <units/isq/si/fps/time.h>
 #include <units/isq/si/fps/volume.h>
+#include <units/isq/si/international/speed.h>
 #include <units/isq/si/length.h>
 #include <units/isq/si/mass.h>
 #include <units/isq/si/power.h>
@@ -76,8 +77,9 @@ void print_details(std::string_view description, const Ship& ship)
                                fmt_line<si::fps::length<si::fps::yard>, si::length<si::metre>>(ship.beam))
             << STD_FMT::format("{:20} : {}\n", "mass",
                                fmt_line<si::fps::mass<si::fps::long_ton>, si::mass<si::tonne>>(ship.mass))
-            << STD_FMT::format("{:20} : {}\n", "speed",
-                               fmt_line<si::fps::speed<si::fps::knot>, si::speed<si::kilometre_per_hour>>(ship.speed))
+            << STD_FMT::format(
+                 "{:20} : {}\n", "speed",
+                 fmt_line<si::speed<si::international::knot>, si::speed<si::kilometre_per_hour>>(ship.speed))
             << STD_FMT::format("{:20} : {}\n", "power",
                                fmt_line<si::fps::power<si::fps::horse_power>, si::power<si::kilowatt>>(ship.power))
             << STD_FMT::format("{:20} : {}\n", "main guns",
@@ -112,7 +114,7 @@ int main()
   auto iowa = Ship{.length{860. * ft},
                    .draft{37. * ft + 2. * in},
                    .beam{108. * ft + 2. * in},
-                   .speed{33 * kn},
+                   .speed{33 * units::isq::si::international::references::kn},
                    .mass{57'540 * lton},
                    .mainGuns{16 * in},
                    .shellMass{2700 * lb},
@@ -123,7 +125,7 @@ int main()
   auto kgv = Ship{.length{745.1 * ft},
                   .draft{33. * ft + 7.5 * in},
                   .beam{103.2 * ft + 2.5 * in},
-                  .speed{28.3 * kn},
+                  .speed{28.3 * units::isq::si::international::references::kn},
                   .mass{42'245 * lton},
                   .mainGuns{14 * in},
                   .shellMass{1'590 * lb},

From 88d8192b50ac6fe5d6b3b68fe9d3db421c4b5348 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Tue, 10 May 2022 11:40:54 +0200
Subject: [PATCH 40/68] build(conan): `si-fps` component now correctly depends
 on `si-international`

---
 conanfile.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/conanfile.py b/conanfile.py
index 6eeb8e75..a0582e42 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -199,7 +199,7 @@ class MPUnitsConan(ConanFile):
         self.cpp_info.components["si-cgs"].requires = ["si"]
         self.cpp_info.components["si-cgs"].includedirs = ["include"]
 
-        self.cpp_info.components["si-fps"].requires = ["si"]
+        self.cpp_info.components["si-fps"].requires = ["si-international"]
         self.cpp_info.components["si-fps"].includedirs = ["include"]
 
         self.cpp_info.components["si-hep"].requires = ["si"]

From 8d0b643bb3a5dcec64c1d71052231f977ca29ecd Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 11:10:15 +0200
Subject: [PATCH 41/68] refactor: :boom: !`named_derived_unit` removed as it
 was not used

---
 src/core/include/units/unit.h | 23 -----------------------
 1 file changed, 23 deletions(-)

diff --git a/src/core/include/units/unit.h b/src/core/include/units/unit.h
index 81cec37b..be9c3ff2 100644
--- a/src/core/include/units/unit.h
+++ b/src/core/include/units/unit.h
@@ -161,29 +161,6 @@ struct derived_unit : downcast_dispatch<Child, detail::derived_unit<Dim, U, URes
   using prefix_family = no_prefix;
 };
 
-/**
- * @brief A named unit with a deduced ratio
- *
- * Defines a new unit with a deduced ratio and the given symbol based on the recipe from the provided
- * derived dimension. The number and order of provided units should match the recipe of the
- * derived dimension. All of the units provided should also be a named ones so it is possible
- * to create a deduced symbol text.
- *
- * @tparam Child inherited class type used by the downcasting facility (CRTP Idiom)
- * @tparam Dim a derived dimension recipe to use for deduction
- * @tparam Symbol a short text representation of the unit
- * @tparam PF no_prefix or a type of prefix family
- * @tparam U the unit of the first composite dimension from provided derived dimension's recipe
- * @tparam URest the units for the rest of dimensions from the recipe
- */
-template<typename Child, DerivedDimension Dim, basic_symbol_text Symbol, PrefixFamily PF, Unit U, Unit... URest>
-  requires detail::same_scaled_units<typename Dim::recipe, U, URest...>
-struct named_derived_unit : downcast_dispatch<Child, detail::derived_unit<Dim, U, URest...>> {
-  static constexpr bool is_named = true;
-  static constexpr auto symbol = Symbol;
-  using prefix_family = PF;
-};
-
 /**
  * @brief An aliased named unit
  *

From f5d21a071142fbdd3b684ffb47ef1647d2540a40 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 11:23:18 +0200
Subject: [PATCH 42/68] refactor: :boom: ! `derived_unit` renamed to
 `derived_deduced_unit`

---
 ...{derived_unit.h => derived_deduced_unit.h} |  5 ++-
 src/core/include/units/unit.h                 |  4 +-
 .../units/isq/iec80000/transfer_rate.h        | 16 ++++----
 .../si-fps/include/units/isq/si/fps/energy.h  |  2 +-
 .../si-fps/include/units/isq/si/fps/power.h   |  3 +-
 .../si-fps/include/units/isq/si/fps/speed.h   |  4 +-
 .../si-fps/include/units/isq/si/fps/volume.h  |  2 +-
 .../include/units/isq/si/international/area.h |  2 +-
 .../units/isq/si/international/speed.h        |  4 +-
 .../units/isq/si/international/volume.h       |  2 +-
 src/systems/si/include/units/isq/si/area.h    | 40 +++++++++----------
 src/systems/si/include/units/isq/si/speed.h   |  2 +-
 src/systems/si/include/units/isq/si/volume.h  | 40 +++++++++----------
 test/unit_test/runtime/fmt_test.cpp           |  2 +-
 test/unit_test/static/custom_unit_test.cpp    |  2 +-
 test/unit_test/static/unit_test.cpp           |  2 +-
 16 files changed, 67 insertions(+), 65 deletions(-)
 rename src/core/include/units/bits/{derived_unit.h => derived_deduced_unit.h} (92%)

diff --git a/src/core/include/units/bits/derived_unit.h b/src/core/include/units/bits/derived_deduced_unit.h
similarity index 92%
rename from src/core/include/units/bits/derived_unit.h
rename to src/core/include/units/bits/derived_deduced_unit.h
index f078c26c..86f3f523 100644
--- a/src/core/include/units/bits/derived_unit.h
+++ b/src/core/include/units/bits/derived_deduced_unit.h
@@ -33,7 +33,7 @@ inline constexpr bool same_scaled_units = false;
 template<typename... Es, Unit... Us>
 inline constexpr bool same_scaled_units<exponent_list<Es...>, Us...> = (UnitOf<Us, typename Es::dimension> && ...);
 
-// derived_unit
+// derived_deduced_unit
 
 template<Exponent E>
 constexpr ratio inverse_if_negative(const ratio& r)
@@ -52,6 +52,7 @@ constexpr ratio derived_ratio(exponent_list<Es...>)
 }
 
 template<DerivedDimension D, Unit... Us>
-using derived_unit = scaled_unit<derived_ratio<Us...>(typename D::recipe()), typename D::coherent_unit::reference>;
+using derived_deduced_unit =
+  scaled_unit<derived_ratio<Us...>(typename D::recipe()), typename D::coherent_unit::reference>;
 
 }  // namespace units::detail
diff --git a/src/core/include/units/unit.h b/src/core/include/units/unit.h
index be9c3ff2..278c9c7c 100644
--- a/src/core/include/units/unit.h
+++ b/src/core/include/units/unit.h
@@ -26,7 +26,7 @@
 #include <units/bits/external/downcasting.h>
 
 // IWYU pragma: begin_exports
-#include <units/bits/derived_unit.h>
+#include <units/bits/derived_deduced_unit.h>
 #include <units/bits/external/fixed_string.h>
 #include <units/prefix.h>
 #include <units/ratio.h>
@@ -155,7 +155,7 @@ struct prefixed_unit : downcast_dispatch<Child, scaled_unit<P::ratio * U::ratio,
 template<typename Child, DerivedDimension Dim, Unit U, Unit... URest>
   requires detail::same_scaled_units<typename Dim::recipe, U, URest...> &&
            (U::is_named && (URest::is_named && ... && true))
-struct derived_unit : downcast_dispatch<Child, detail::derived_unit<Dim, U, URest...>> {
+struct derived_deduced_unit : downcast_dispatch<Child, detail::derived_deduced_unit<Dim, U, URest...>> {
   static constexpr bool is_named = false;
   static constexpr auto symbol = detail::derived_symbol_text<Dim, U, URest...>();
   using prefix_family = no_prefix;
diff --git a/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h b/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h
index bd2bb20c..0cd87928 100644
--- a/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h
+++ b/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h
@@ -39,14 +39,14 @@ struct dim_transfer_rate :
     derived_dimension<dim_transfer_rate, byte_per_second, exponent<dim_storage_capacity, 1>,
                       exponent<si::dim_time, -1>> {};
 
-struct kilobyte_per_second : derived_unit<kilobyte_per_second, dim_transfer_rate, kilobyte, si::second> {};
-struct megabyte_per_second : derived_unit<megabyte_per_second, dim_transfer_rate, megabyte, si::second> {};
-struct gigabyte_per_second : derived_unit<gigabyte_per_second, dim_transfer_rate, gigabyte, si::second> {};
-struct terabyte_per_second : derived_unit<terabyte_per_second, dim_transfer_rate, terabyte, si::second> {};
-struct petabyte_per_second : derived_unit<petabyte_per_second, dim_transfer_rate, petabyte, si::second> {};
-struct exabyte_per_second : derived_unit<exabyte_per_second, dim_transfer_rate, exabyte, si::second> {};
-struct zettabyte_per_second : derived_unit<zettabyte_per_second, dim_transfer_rate, zettabyte, si::second> {};
-struct yottabyte_per_second : derived_unit<yottabyte_per_second, dim_transfer_rate, yottabyte, si::second> {};
+struct kilobyte_per_second : derived_deduced_unit<kilobyte_per_second, dim_transfer_rate, kilobyte, si::second> {};
+struct megabyte_per_second : derived_deduced_unit<megabyte_per_second, dim_transfer_rate, megabyte, si::second> {};
+struct gigabyte_per_second : derived_deduced_unit<gigabyte_per_second, dim_transfer_rate, gigabyte, si::second> {};
+struct terabyte_per_second : derived_deduced_unit<terabyte_per_second, dim_transfer_rate, terabyte, si::second> {};
+struct petabyte_per_second : derived_deduced_unit<petabyte_per_second, dim_transfer_rate, petabyte, si::second> {};
+struct exabyte_per_second : derived_deduced_unit<exabyte_per_second, dim_transfer_rate, exabyte, si::second> {};
+struct zettabyte_per_second : derived_deduced_unit<zettabyte_per_second, dim_transfer_rate, zettabyte, si::second> {};
+struct yottabyte_per_second : derived_deduced_unit<yottabyte_per_second, dim_transfer_rate, yottabyte, si::second> {};
 
 template<typename T>
 concept TransferRate = QuantityOf<T, dim_transfer_rate>;
diff --git a/src/systems/si-fps/include/units/isq/si/fps/energy.h b/src/systems/si-fps/include/units/isq/si/fps/energy.h
index 7278f016..f0f69c65 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/energy.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/energy.h
@@ -40,7 +40,7 @@ struct foot_poundal : unit<foot_poundal> {};
 struct dim_energy : isq::dim_energy<dim_energy, foot_poundal, dim_length, dim_force> {};
 
 // https://en.wikipedia.org/wiki/Foot-pound_(energy)
-struct foot_pound_force : derived_unit<foot_pound_force, dim_energy, foot, pound_force> {};
+struct foot_pound_force : derived_deduced_unit<foot_pound_force, dim_energy, foot, pound_force> {};
 
 template<UnitOf<dim_energy> U, Representation Rep = double>
 using energy = quantity<dim_energy, U, Rep>;
diff --git a/src/systems/si-fps/include/units/isq/si/fps/power.h b/src/systems/si-fps/include/units/isq/si/fps/power.h
index d48d1f31..37fe6ff7 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/power.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/power.h
@@ -39,7 +39,8 @@ struct foot_poundal_per_second : unit<foot_poundal_per_second> {};
 
 struct dim_power : isq::dim_power<dim_power, foot_poundal_per_second, dim_length, dim_force, dim_time> {};
 
-struct foot_pound_force_per_second : derived_unit<foot_pound_force_per_second, dim_power, foot, pound_force, second> {};
+struct foot_pound_force_per_second :
+    derived_deduced_unit<foot_pound_force_per_second, dim_power, foot, pound_force, second> {};
 
 struct horse_power : named_scaled_unit<horse_power, "hp", no_prefix, ratio(550), foot_pound_force_per_second> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/speed.h b/src/systems/si-fps/include/units/isq/si/fps/speed.h
index 816aff3a..a2577253 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/speed.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/speed.h
@@ -41,8 +41,8 @@ struct dim_speed : isq::dim_speed<dim_speed, foot_per_second, dim_length, dim_ti
 template<UnitOf<dim_speed> U, Representation Rep = double>
 using speed = quantity<dim_speed, U, Rep>;
 
-struct mile_per_hour : derived_unit<mile_per_hour, dim_speed, mile, hour> {};
-struct nautical_mile_per_hour : derived_unit<nautical_mile_per_hour, dim_speed, nautical_mile, hour> {};
+struct mile_per_hour : derived_deduced_unit<mile_per_hour, dim_speed, mile, hour> {};
+struct nautical_mile_per_hour : derived_deduced_unit<nautical_mile_per_hour, dim_speed, nautical_mile, hour> {};
 struct knot : alias_unit<nautical_mile_per_hour, "kn", no_prefix> {};
 
 #ifndef UNITS_NO_LITERALS
diff --git a/src/systems/si-fps/include/units/isq/si/fps/volume.h b/src/systems/si-fps/include/units/isq/si/fps/volume.h
index a461790c..b7b813a6 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/volume.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/volume.h
@@ -37,7 +37,7 @@ namespace units::isq::si::fps {
 struct cubic_foot : unit<cubic_foot> {};
 struct dim_volume : isq::dim_volume<dim_volume, cubic_foot, dim_length> {};
 
-struct cubic_yard : derived_unit<cubic_yard, dim_volume, yard> {};
+struct cubic_yard : derived_deduced_unit<cubic_yard, dim_volume, yard> {};
 
 template<UnitOf<dim_volume> U, Representation Rep = double>
 using volume = quantity<dim_volume, U, Rep>;
diff --git a/src/systems/si-international/include/units/isq/si/international/area.h b/src/systems/si-international/include/units/isq/si/international/area.h
index 74bd6ad1..ce30183c 100644
--- a/src/systems/si-international/include/units/isq/si/international/area.h
+++ b/src/systems/si-international/include/units/isq/si/international/area.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si::international {
 
-struct square_foot : derived_unit<square_foot, si::dim_area, si::international::foot> {};
+struct square_foot : derived_deduced_unit<square_foot, si::dim_area, si::international::foot> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si-international/include/units/isq/si/international/speed.h b/src/systems/si-international/include/units/isq/si/international/speed.h
index 1f81a592..16ef5a66 100644
--- a/src/systems/si-international/include/units/isq/si/international/speed.h
+++ b/src/systems/si-international/include/units/isq/si/international/speed.h
@@ -34,9 +34,9 @@
 
 namespace units::isq::si::international {
 
-struct mile_per_hour : derived_unit<mile_per_hour, si::dim_speed, si::international::mile, si::hour> {};
+struct mile_per_hour : derived_deduced_unit<mile_per_hour, si::dim_speed, si::international::mile, si::hour> {};
 struct nautical_mile_per_hour :
-    derived_unit<nautical_mile_per_hour, si::dim_speed, si::international::nautical_mile, si::hour> {};
+    derived_deduced_unit<nautical_mile_per_hour, si::dim_speed, si::international::nautical_mile, si::hour> {};
 struct knot : alias_unit<nautical_mile_per_hour, "kn", no_prefix> {};
 
 #ifndef UNITS_NO_LITERALS
diff --git a/src/systems/si-international/include/units/isq/si/international/volume.h b/src/systems/si-international/include/units/isq/si/international/volume.h
index 7c7b65cc..f4a5e5d5 100644
--- a/src/systems/si-international/include/units/isq/si/international/volume.h
+++ b/src/systems/si-international/include/units/isq/si/international/volume.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si::international {
 
-struct cubic_foot : derived_unit<cubic_foot, si::dim_volume, si::international::foot> {};
+struct cubic_foot : derived_deduced_unit<cubic_foot, si::dim_volume, si::international::foot> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si/include/units/isq/si/area.h b/src/systems/si/include/units/isq/si/area.h
index a321fdda..cd6efb2b 100644
--- a/src/systems/si/include/units/isq/si/area.h
+++ b/src/systems/si/include/units/isq/si/area.h
@@ -37,26 +37,26 @@ namespace units::isq::si {
 struct square_metre : unit<square_metre> {};
 struct dim_area : isq::dim_area<dim_area, square_metre, dim_length> {};
 
-struct square_yoctometre : derived_unit<square_yoctometre, dim_area, yoctometre> {};
-struct square_zeptometre : derived_unit<square_zeptometre, dim_area, zeptometre> {};
-struct square_attometre : derived_unit<square_attometre, dim_area, attometre> {};
-struct square_femtometre : derived_unit<square_femtometre, dim_area, femtometre> {};
-struct square_picometre : derived_unit<square_picometre, dim_area, picometre> {};
-struct square_nanometre : derived_unit<square_nanometre, dim_area, nanometre> {};
-struct square_micrometre : derived_unit<square_micrometre, dim_area, micrometre> {};
-struct square_millimetre : derived_unit<square_millimetre, dim_area, millimetre> {};
-struct square_centimetre : derived_unit<square_centimetre, dim_area, centimetre> {};
-struct square_decimetre : derived_unit<square_decimetre, dim_area, decimetre> {};
-struct square_decametre : derived_unit<square_decametre, dim_area, decametre> {};
-struct square_hectometre : derived_unit<square_hectometre, dim_area, hectometre> {};
-struct square_kilometre : derived_unit<square_kilometre, dim_area, kilometre> {};
-struct square_megametre : derived_unit<square_megametre, dim_area, megametre> {};
-struct square_gigametre : derived_unit<square_gigametre, dim_area, gigametre> {};
-struct square_terametre : derived_unit<square_terametre, dim_area, terametre> {};
-struct square_petametre : derived_unit<square_petametre, dim_area, petametre> {};
-struct square_exametre : derived_unit<square_exametre, dim_area, exametre> {};
-struct square_zettametre : derived_unit<square_zettametre, dim_area, zettametre> {};
-struct square_yottametre : derived_unit<square_yottametre, dim_area, yottametre> {};
+struct square_yoctometre : derived_deduced_unit<square_yoctometre, dim_area, yoctometre> {};
+struct square_zeptometre : derived_deduced_unit<square_zeptometre, dim_area, zeptometre> {};
+struct square_attometre : derived_deduced_unit<square_attometre, dim_area, attometre> {};
+struct square_femtometre : derived_deduced_unit<square_femtometre, dim_area, femtometre> {};
+struct square_picometre : derived_deduced_unit<square_picometre, dim_area, picometre> {};
+struct square_nanometre : derived_deduced_unit<square_nanometre, dim_area, nanometre> {};
+struct square_micrometre : derived_deduced_unit<square_micrometre, dim_area, micrometre> {};
+struct square_millimetre : derived_deduced_unit<square_millimetre, dim_area, millimetre> {};
+struct square_centimetre : derived_deduced_unit<square_centimetre, dim_area, centimetre> {};
+struct square_decimetre : derived_deduced_unit<square_decimetre, dim_area, decimetre> {};
+struct square_decametre : derived_deduced_unit<square_decametre, dim_area, decametre> {};
+struct square_hectometre : derived_deduced_unit<square_hectometre, dim_area, hectometre> {};
+struct square_kilometre : derived_deduced_unit<square_kilometre, dim_area, kilometre> {};
+struct square_megametre : derived_deduced_unit<square_megametre, dim_area, megametre> {};
+struct square_gigametre : derived_deduced_unit<square_gigametre, dim_area, gigametre> {};
+struct square_terametre : derived_deduced_unit<square_terametre, dim_area, terametre> {};
+struct square_petametre : derived_deduced_unit<square_petametre, dim_area, petametre> {};
+struct square_exametre : derived_deduced_unit<square_exametre, dim_area, exametre> {};
+struct square_zettametre : derived_deduced_unit<square_zettametre, dim_area, zettametre> {};
+struct square_yottametre : derived_deduced_unit<square_yottametre, dim_area, yottametre> {};
 
 struct are : alias_unit<square_decametre, "a", prefix> {};
 struct centiare : prefixed_alias_unit<square_metre, centi, are> {};
diff --git a/src/systems/si/include/units/isq/si/speed.h b/src/systems/si/include/units/isq/si/speed.h
index 4d03d36b..ddb022cd 100644
--- a/src/systems/si/include/units/isq/si/speed.h
+++ b/src/systems/si/include/units/isq/si/speed.h
@@ -37,7 +37,7 @@ namespace units::isq::si {
 struct metre_per_second : unit<metre_per_second> {};
 struct dim_speed : isq::dim_speed<dim_speed, metre_per_second, dim_length, dim_time> {};
 
-struct kilometre_per_hour : derived_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
+struct kilometre_per_hour : derived_deduced_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
 
 template<UnitOf<dim_speed> U, Representation Rep = double>
 using speed = quantity<dim_speed, U, Rep>;
diff --git a/src/systems/si/include/units/isq/si/volume.h b/src/systems/si/include/units/isq/si/volume.h
index 8430e60b..6f0dc9b1 100644
--- a/src/systems/si/include/units/isq/si/volume.h
+++ b/src/systems/si/include/units/isq/si/volume.h
@@ -37,26 +37,26 @@ namespace units::isq::si {
 struct cubic_metre : unit<cubic_metre> {};
 struct dim_volume : isq::dim_volume<dim_volume, cubic_metre, dim_length> {};
 
-struct cubic_yoctometre : derived_unit<cubic_yoctometre, dim_volume, yoctometre> {};
-struct cubic_zeptometre : derived_unit<cubic_zeptometre, dim_volume, zeptometre> {};
-struct cubic_attometre : derived_unit<cubic_attometre, dim_volume, attometre> {};
-struct cubic_femtometre : derived_unit<cubic_femtometre, dim_volume, femtometre> {};
-struct cubic_picometre : derived_unit<cubic_picometre, dim_volume, picometre> {};
-struct cubic_nanometre : derived_unit<cubic_nanometre, dim_volume, nanometre> {};
-struct cubic_micrometre : derived_unit<cubic_micrometre, dim_volume, micrometre> {};
-struct cubic_millimetre : derived_unit<cubic_millimetre, dim_volume, millimetre> {};
-struct cubic_centimetre : derived_unit<cubic_centimetre, dim_volume, centimetre> {};
-struct cubic_decimetre : derived_unit<cubic_decimetre, dim_volume, decimetre> {};
-struct cubic_decametre : derived_unit<cubic_decametre, dim_volume, decametre> {};
-struct cubic_hectometre : derived_unit<cubic_hectometre, dim_volume, hectometre> {};
-struct cubic_kilometre : derived_unit<cubic_kilometre, dim_volume, kilometre> {};
-struct cubic_megametre : derived_unit<cubic_megametre, dim_volume, megametre> {};
-struct cubic_gigametre : derived_unit<cubic_gigametre, dim_volume, gigametre> {};
-struct cubic_terametre : derived_unit<cubic_terametre, dim_volume, terametre> {};
-struct cubic_petametre : derived_unit<cubic_petametre, dim_volume, petametre> {};
-struct cubic_exametre : derived_unit<cubic_exametre, dim_volume, exametre> {};
-struct cubic_zettametre : derived_unit<cubic_zettametre, dim_volume, zettametre> {};
-struct cubic_yottametre : derived_unit<cubic_yottametre, dim_volume, yottametre> {};
+struct cubic_yoctometre : derived_deduced_unit<cubic_yoctometre, dim_volume, yoctometre> {};
+struct cubic_zeptometre : derived_deduced_unit<cubic_zeptometre, dim_volume, zeptometre> {};
+struct cubic_attometre : derived_deduced_unit<cubic_attometre, dim_volume, attometre> {};
+struct cubic_femtometre : derived_deduced_unit<cubic_femtometre, dim_volume, femtometre> {};
+struct cubic_picometre : derived_deduced_unit<cubic_picometre, dim_volume, picometre> {};
+struct cubic_nanometre : derived_deduced_unit<cubic_nanometre, dim_volume, nanometre> {};
+struct cubic_micrometre : derived_deduced_unit<cubic_micrometre, dim_volume, micrometre> {};
+struct cubic_millimetre : derived_deduced_unit<cubic_millimetre, dim_volume, millimetre> {};
+struct cubic_centimetre : derived_deduced_unit<cubic_centimetre, dim_volume, centimetre> {};
+struct cubic_decimetre : derived_deduced_unit<cubic_decimetre, dim_volume, decimetre> {};
+struct cubic_decametre : derived_deduced_unit<cubic_decametre, dim_volume, decametre> {};
+struct cubic_hectometre : derived_deduced_unit<cubic_hectometre, dim_volume, hectometre> {};
+struct cubic_kilometre : derived_deduced_unit<cubic_kilometre, dim_volume, kilometre> {};
+struct cubic_megametre : derived_deduced_unit<cubic_megametre, dim_volume, megametre> {};
+struct cubic_gigametre : derived_deduced_unit<cubic_gigametre, dim_volume, gigametre> {};
+struct cubic_terametre : derived_deduced_unit<cubic_terametre, dim_volume, terametre> {};
+struct cubic_petametre : derived_deduced_unit<cubic_petametre, dim_volume, petametre> {};
+struct cubic_exametre : derived_deduced_unit<cubic_exametre, dim_volume, exametre> {};
+struct cubic_zettametre : derived_deduced_unit<cubic_zettametre, dim_volume, zettametre> {};
+struct cubic_yottametre : derived_deduced_unit<cubic_yottametre, dim_volume, yottametre> {};
 
 struct litre : alias_unit<cubic_decimetre, "l", prefix> {};
 struct yoctolitre : prefixed_alias_unit<cubic_nanometre, yocto, litre> {};
diff --git a/test/unit_test/runtime/fmt_test.cpp b/test/unit_test/runtime/fmt_test.cpp
index abc595e6..78cb6a25 100644
--- a/test/unit_test/runtime/fmt_test.cpp
+++ b/test/unit_test/runtime/fmt_test.cpp
@@ -189,7 +189,7 @@ TEST_CASE("operator<< on a quantity", "[text][ostream][fmt]")
       SECTION("surface tension")
       {
         struct newton_per_centimetre :
-            derived_unit<newton_per_centimetre, si::dim_surface_tension, newton, centimetre> {};
+            derived_deduced_unit<newton_per_centimetre, si::dim_surface_tension, newton, centimetre> {};
         const surface_tension<newton_per_centimetre> q(123);
         os << q;
 
diff --git a/test/unit_test/static/custom_unit_test.cpp b/test/unit_test/static/custom_unit_test.cpp
index 9ea04d20..15216be8 100644
--- a/test/unit_test/static/custom_unit_test.cpp
+++ b/test/unit_test/static/custom_unit_test.cpp
@@ -73,7 +73,7 @@ struct kilogram_per_second : unit<kilogram_per_second> {};
 struct dim_mass_rate :
     derived_dimension<dim_mass_rate, kilogram_per_second, units::exponent<dim_mass, 1>, units::exponent<dim_time, -1>> {
 };
-struct kilogram_per_hour : derived_unit<kilogram_per_hour, dim_mass_rate, kilogram, hour> {};
+struct kilogram_per_hour : derived_deduced_unit<kilogram_per_hour, dim_mass_rate, kilogram, hour> {};
 [[maybe_unused]] constexpr auto a = 1_q_kg / 1_q_h;
 
 }  // namespace
diff --git a/test/unit_test/static/unit_test.cpp b/test/unit_test/static/unit_test.cpp
index 4856b09a..059ef739 100644
--- a/test/unit_test/static/unit_test.cpp
+++ b/test/unit_test/static/unit_test.cpp
@@ -55,7 +55,7 @@ static_assert([]<Prefix P>(P) {
 struct metre_per_second : unit<metre_per_second> {};
 struct dim_speed :
     derived_dimension<dim_speed, metre_per_second, units::exponent<dim_length, 1>, units::exponent<dim_time, -1>> {};
-struct kilometre_per_hour : derived_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
+struct kilometre_per_hour : derived_deduced_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
 
 static_assert(equivalent<metre::named_unit, metre>);
 static_assert(equivalent<metre::scaled_unit, metre>);

From 0522bae972c56fa5a57ce7f28f3536576eeacba7 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 11:40:19 +0200
Subject: [PATCH 43/68] refactor: :boom: ! `unit` renamed to `derived_unit`

---
 src/core/include/units/unit.h                 | 30 +++++++++----------
 .../units/isq/iec80000/transfer_rate.h        |  2 +-
 .../si-cgs/include/units/isq/si/cgs/power.h   |  2 +-
 .../si-cgs/include/units/isq/si/cgs/speed.h   |  2 +-
 .../include/units/isq/si/fps/acceleration.h   |  2 +-
 .../si-fps/include/units/isq/si/fps/area.h    |  2 +-
 .../si-fps/include/units/isq/si/fps/density.h |  2 +-
 .../si-fps/include/units/isq/si/fps/energy.h  |  2 +-
 .../si-fps/include/units/isq/si/fps/power.h   |  2 +-
 .../include/units/isq/si/fps/pressure.h       |  2 +-
 .../si-fps/include/units/isq/si/fps/speed.h   |  2 +-
 .../si-fps/include/units/isq/si/fps/volume.h  |  2 +-
 .../include/units/isq/si/hep/momentum.h       |  2 +-
 .../si/include/units/isq/si/acceleration.h    |  2 +-
 src/systems/si/include/units/isq/si/area.h    |  2 +-
 .../si/include/units/isq/si/charge_density.h  |  4 +--
 .../si/include/units/isq/si/concentration.h   |  2 +-
 .../si/include/units/isq/si/current_density.h |  2 +-
 src/systems/si/include/units/isq/si/density.h |  2 +-
 .../include/units/isq/si/dynamic_viscosity.h  |  2 +-
 .../units/isq/si/electric_field_strength.h    |  2 +-
 .../si/include/units/isq/si/energy_density.h  |  2 +-
 .../si/include/units/isq/si/heat_capacity.h   |  6 ++--
 .../si/include/units/isq/si/luminance.h       |  2 +-
 .../si/include/units/isq/si/molar_energy.h    |  2 +-
 .../si/include/units/isq/si/momentum.h        |  2 +-
 .../si/include/units/isq/si/permeability.h    |  2 +-
 .../si/include/units/isq/si/permittivity.h    |  2 +-
 src/systems/si/include/units/isq/si/speed.h   |  2 +-
 .../si/include/units/isq/si/surface_tension.h |  2 +-
 .../units/isq/si/thermal_conductivity.h       |  2 +-
 src/systems/si/include/units/isq/si/torque.h  |  2 +-
 src/systems/si/include/units/isq/si/volume.h  |  2 +-
 test/unit_test/static/custom_unit_test.cpp    |  6 ++--
 test/unit_test/static/unit_test.cpp           |  2 +-
 35 files changed, 54 insertions(+), 54 deletions(-)

diff --git a/src/core/include/units/unit.h b/src/core/include/units/unit.h
index 278c9c7c..f2faf55d 100644
--- a/src/core/include/units/unit.h
+++ b/src/core/include/units/unit.h
@@ -65,20 +65,6 @@ using downcast_unit = downcast<scaled_unit<R, typename dimension_unit<D>::refere
 template<Unit U1, Unit U2>
 struct same_unit_reference : is_same<typename U1::reference, typename U2::reference> {};
 
-/**
- * @brief An unnamed unit
- *
- * Defines a new unnamed (in most cases coherent) derived unit of a specific derived dimension
- * and it should be passed in this dimension's definition.
- *
- * @tparam Child inherited class type used by the downcasting facility (CRTP Idiom)
- */
-template<typename Child>
-struct unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {
-  static constexpr bool is_named = false;
-  using prefix_family = no_prefix;
-};
-
 /**
  * @brief A named unit
  *
@@ -139,6 +125,20 @@ struct prefixed_unit : downcast_dispatch<Child, scaled_unit<P::ratio * U::ratio,
   using prefix_family = no_prefix;
 };
 
+/**
+ * @brief A coherent unit of a derived quantity
+ *
+ * Defines a new coherent unit of a derived quantity. It should be passed as a coherent unit
+ * in the dimension's definition for such a quantity.
+ *
+ * @tparam Child inherited class type used by the downcasting facility (CRTP Idiom)
+ */
+template<typename Child>
+struct derived_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {
+  static constexpr bool is_named = false;
+  using prefix_family = no_prefix;
+};
+
 /**
  * @brief A unit with a deduced ratio and symbol
  *
@@ -209,6 +209,6 @@ struct prefixed_alias_unit : U {
  *
  * Used as a coherent unit of an unknown dimension.
  */
-struct unknown_coherent_unit : unit<unknown_coherent_unit> {};
+struct unknown_coherent_unit : derived_unit<unknown_coherent_unit> {};
 
 }  // namespace units
diff --git a/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h b/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h
index 0cd87928..ce22f0f3 100644
--- a/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h
+++ b/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::iec80000 {
 
-struct byte_per_second : unit<byte_per_second> {};
+struct byte_per_second : derived_unit<byte_per_second> {};
 struct dim_transfer_rate :
     derived_dimension<dim_transfer_rate, byte_per_second, exponent<dim_storage_capacity, 1>,
                       exponent<si::dim_time, -1>> {};
diff --git a/src/systems/si-cgs/include/units/isq/si/cgs/power.h b/src/systems/si-cgs/include/units/isq/si/cgs/power.h
index 1ac322f6..5d2b0483 100644
--- a/src/systems/si-cgs/include/units/isq/si/cgs/power.h
+++ b/src/systems/si-cgs/include/units/isq/si/cgs/power.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si::cgs {
 
-struct erg_per_second : unit<erg_per_second> {};
+struct erg_per_second : derived_unit<erg_per_second> {};
 
 struct dim_power : isq::dim_power<dim_power, erg_per_second, dim_energy, dim_time> {};
 
diff --git a/src/systems/si-cgs/include/units/isq/si/cgs/speed.h b/src/systems/si-cgs/include/units/isq/si/cgs/speed.h
index 6cdc4a7d..c70ee197 100644
--- a/src/systems/si-cgs/include/units/isq/si/cgs/speed.h
+++ b/src/systems/si-cgs/include/units/isq/si/cgs/speed.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si::cgs {
 
-struct centimetre_per_second : unit<centimetre_per_second> {};
+struct centimetre_per_second : derived_unit<centimetre_per_second> {};
 struct dim_speed : isq::dim_speed<dim_speed, centimetre_per_second, dim_length, dim_time> {};
 
 template<UnitOf<dim_speed> U, Representation Rep = double>
diff --git a/src/systems/si-fps/include/units/isq/si/fps/acceleration.h b/src/systems/si-fps/include/units/isq/si/fps/acceleration.h
index 97990439..da1c9593 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/acceleration.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/acceleration.h
@@ -33,7 +33,7 @@
 
 namespace units::isq::si::fps {
 
-struct foot_per_second_sq : unit<foot_per_second_sq> {};
+struct foot_per_second_sq : derived_unit<foot_per_second_sq> {};
 struct dim_acceleration : isq::dim_acceleration<dim_acceleration, foot_per_second_sq, dim_length, dim_time> {};
 
 template<UnitOf<dim_acceleration> U, Representation Rep = double>
diff --git a/src/systems/si-fps/include/units/isq/si/fps/area.h b/src/systems/si-fps/include/units/isq/si/fps/area.h
index acafd67f..076dab96 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/area.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/area.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si::fps {
 
-struct square_foot : unit<square_foot> {};
+struct square_foot : derived_unit<square_foot> {};
 struct dim_area : isq::dim_area<dim_area, square_foot, dim_length> {};
 
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/density.h b/src/systems/si-fps/include/units/isq/si/fps/density.h
index f2aa0e65..41ee340e 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/density.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/density.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si::fps {
 
-struct pound_per_foot_cub : unit<pound_per_foot_cub> {};
+struct pound_per_foot_cub : derived_unit<pound_per_foot_cub> {};
 
 struct dim_density : isq::dim_density<dim_density, pound_per_foot_cub, dim_mass, dim_length> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/energy.h b/src/systems/si-fps/include/units/isq/si/fps/energy.h
index f0f69c65..94bdac0d 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/energy.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/energy.h
@@ -35,7 +35,7 @@
 namespace units::isq::si::fps {
 
 // https://en.wikipedia.org/wiki/Foot-poundal
-struct foot_poundal : unit<foot_poundal> {};
+struct foot_poundal : derived_unit<foot_poundal> {};
 
 struct dim_energy : isq::dim_energy<dim_energy, foot_poundal, dim_length, dim_force> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/power.h b/src/systems/si-fps/include/units/isq/si/fps/power.h
index 37fe6ff7..d168ac6d 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/power.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/power.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si::fps {
 
-struct foot_poundal_per_second : unit<foot_poundal_per_second> {};
+struct foot_poundal_per_second : derived_unit<foot_poundal_per_second> {};
 
 struct dim_power : isq::dim_power<dim_power, foot_poundal_per_second, dim_length, dim_force, dim_time> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/pressure.h b/src/systems/si-fps/include/units/isq/si/fps/pressure.h
index 2c87269f..84658252 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/pressure.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/pressure.h
@@ -36,7 +36,7 @@
 
 namespace units::isq::si::fps {
 
-struct poundal_per_foot_sq : unit<poundal_per_foot_sq> {};
+struct poundal_per_foot_sq : derived_unit<poundal_per_foot_sq> {};
 
 struct dim_pressure : isq::dim_pressure<dim_pressure, poundal_per_foot_sq, dim_force, dim_area> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/speed.h b/src/systems/si-fps/include/units/isq/si/fps/speed.h
index a2577253..0fb4fbb4 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/speed.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/speed.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si::fps {
 
-struct foot_per_second : unit<foot_per_second> {};
+struct foot_per_second : derived_unit<foot_per_second> {};
 struct dim_speed : isq::dim_speed<dim_speed, foot_per_second, dim_length, dim_time> {};
 
 template<UnitOf<dim_speed> U, Representation Rep = double>
diff --git a/src/systems/si-fps/include/units/isq/si/fps/volume.h b/src/systems/si-fps/include/units/isq/si/fps/volume.h
index b7b813a6..c1ca9c72 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/volume.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/volume.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si::fps {
 
-struct cubic_foot : unit<cubic_foot> {};
+struct cubic_foot : derived_unit<cubic_foot> {};
 struct dim_volume : isq::dim_volume<dim_volume, cubic_foot, dim_length> {};
 
 struct cubic_yard : derived_deduced_unit<cubic_yard, dim_volume, yard> {};
diff --git a/src/systems/si-hep/include/units/isq/si/hep/momentum.h b/src/systems/si-hep/include/units/isq/si/hep/momentum.h
index 74a85390..26417868 100644
--- a/src/systems/si-hep/include/units/isq/si/hep/momentum.h
+++ b/src/systems/si-hep/include/units/isq/si/hep/momentum.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si::hep {
 
-struct kilogram_metre_per_second : unit<kilogram_metre_per_second> {};
+struct kilogram_metre_per_second : derived_unit<kilogram_metre_per_second> {};
 
 struct eV_per_c :
     named_scaled_unit<eV_per_c, "eV/c", prefix, ratio(5'344'285'992'678, 1'000'000'000'000, -35),
diff --git a/src/systems/si/include/units/isq/si/acceleration.h b/src/systems/si/include/units/isq/si/acceleration.h
index 313c1df5..90f0168a 100644
--- a/src/systems/si/include/units/isq/si/acceleration.h
+++ b/src/systems/si/include/units/isq/si/acceleration.h
@@ -33,7 +33,7 @@
 
 namespace units::isq::si {
 
-struct metre_per_second_sq : unit<metre_per_second_sq> {};
+struct metre_per_second_sq : derived_unit<metre_per_second_sq> {};
 struct dim_acceleration : isq::dim_acceleration<dim_acceleration, metre_per_second_sq, dim_length, dim_time> {};
 
 template<UnitOf<dim_acceleration> U, Representation Rep = double>
diff --git a/src/systems/si/include/units/isq/si/area.h b/src/systems/si/include/units/isq/si/area.h
index cd6efb2b..a3818096 100644
--- a/src/systems/si/include/units/isq/si/area.h
+++ b/src/systems/si/include/units/isq/si/area.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct square_metre : unit<square_metre> {};
+struct square_metre : derived_unit<square_metre> {};
 struct dim_area : isq::dim_area<dim_area, square_metre, dim_length> {};
 
 struct square_yoctometre : derived_deduced_unit<square_yoctometre, dim_area, yoctometre> {};
diff --git a/src/systems/si/include/units/isq/si/charge_density.h b/src/systems/si/include/units/isq/si/charge_density.h
index b50d0c03..52fba248 100644
--- a/src/systems/si/include/units/isq/si/charge_density.h
+++ b/src/systems/si/include/units/isq/si/charge_density.h
@@ -35,8 +35,8 @@
 
 namespace units::isq::si {
 
-struct coulomb_per_metre_cub : unit<coulomb_per_metre_cub> {};
-struct coulomb_per_metre_sq : unit<coulomb_per_metre_sq> {};
+struct coulomb_per_metre_cub : derived_unit<coulomb_per_metre_cub> {};
+struct coulomb_per_metre_sq : derived_unit<coulomb_per_metre_sq> {};
 
 struct dim_charge_density :
     isq::dim_charge_density<dim_charge_density, coulomb_per_metre_cub, dim_electric_charge, dim_length> {};
diff --git a/src/systems/si/include/units/isq/si/concentration.h b/src/systems/si/include/units/isq/si/concentration.h
index d59b3143..732583a5 100644
--- a/src/systems/si/include/units/isq/si/concentration.h
+++ b/src/systems/si/include/units/isq/si/concentration.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct mol_per_metre_cub : unit<mol_per_metre_cub> {};
+struct mol_per_metre_cub : derived_unit<mol_per_metre_cub> {};
 struct dim_concentration :
     isq::dim_concentration<dim_concentration, mol_per_metre_cub, dim_amount_of_substance, dim_length> {};
 
diff --git a/src/systems/si/include/units/isq/si/current_density.h b/src/systems/si/include/units/isq/si/current_density.h
index 4017414c..94234b5b 100644
--- a/src/systems/si/include/units/isq/si/current_density.h
+++ b/src/systems/si/include/units/isq/si/current_density.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct ampere_per_metre_sq : unit<ampere_per_metre_sq> {};
+struct ampere_per_metre_sq : derived_unit<ampere_per_metre_sq> {};
 
 struct dim_current_density :
     isq::dim_current_density<dim_current_density, ampere_per_metre_sq, dim_electric_current, dim_length> {};
diff --git a/src/systems/si/include/units/isq/si/density.h b/src/systems/si/include/units/isq/si/density.h
index 9a06b479..d890e225 100644
--- a/src/systems/si/include/units/isq/si/density.h
+++ b/src/systems/si/include/units/isq/si/density.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct kilogram_per_metre_cub : unit<kilogram_per_metre_cub> {};
+struct kilogram_per_metre_cub : derived_unit<kilogram_per_metre_cub> {};
 
 struct dim_density : isq::dim_density<dim_density, kilogram_per_metre_cub, dim_mass, dim_length> {};
 
diff --git a/src/systems/si/include/units/isq/si/dynamic_viscosity.h b/src/systems/si/include/units/isq/si/dynamic_viscosity.h
index 763eb66c..81f0d2bb 100644
--- a/src/systems/si/include/units/isq/si/dynamic_viscosity.h
+++ b/src/systems/si/include/units/isq/si/dynamic_viscosity.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct pascal_second : unit<pascal_second> {};
+struct pascal_second : derived_unit<pascal_second> {};
 struct dim_dynamic_viscosity :
     isq::dim_dynamic_viscosity<dim_dynamic_viscosity, pascal_second, dim_pressure, dim_time> {};
 
diff --git a/src/systems/si/include/units/isq/si/electric_field_strength.h b/src/systems/si/include/units/isq/si/electric_field_strength.h
index 49e843f7..773640d5 100644
--- a/src/systems/si/include/units/isq/si/electric_field_strength.h
+++ b/src/systems/si/include/units/isq/si/electric_field_strength.h
@@ -33,7 +33,7 @@
 
 namespace units::isq::si {
 
-struct volt_per_metre : unit<volt_per_metre> {};
+struct volt_per_metre : derived_unit<volt_per_metre> {};
 struct dim_electric_field_strength :
     isq::dim_electric_field_strength<dim_electric_field_strength, volt_per_metre, dim_voltage, dim_length> {};
 
diff --git a/src/systems/si/include/units/isq/si/energy_density.h b/src/systems/si/include/units/isq/si/energy_density.h
index 3e4e501e..e9e156d7 100644
--- a/src/systems/si/include/units/isq/si/energy_density.h
+++ b/src/systems/si/include/units/isq/si/energy_density.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct joule_per_metre_cub : unit<joule_per_metre_cub> {};
+struct joule_per_metre_cub : derived_unit<joule_per_metre_cub> {};
 struct dim_energy_density : isq::dim_energy_density<dim_energy_density, joule_per_metre_cub, dim_energy, dim_volume> {};
 
 template<UnitOf<dim_energy_density> U, Representation Rep = double>
diff --git a/src/systems/si/include/units/isq/si/heat_capacity.h b/src/systems/si/include/units/isq/si/heat_capacity.h
index b264f59d..5ae30cfa 100644
--- a/src/systems/si/include/units/isq/si/heat_capacity.h
+++ b/src/systems/si/include/units/isq/si/heat_capacity.h
@@ -36,9 +36,9 @@
 
 namespace units::isq::si {
 
-struct joule_per_kelvin : unit<joule_per_kelvin> {};
-struct joule_per_kilogram_kelvin : unit<joule_per_kilogram_kelvin> {};
-struct joule_per_mole_kelvin : unit<joule_per_mole_kelvin> {};
+struct joule_per_kelvin : derived_unit<joule_per_kelvin> {};
+struct joule_per_kilogram_kelvin : derived_unit<joule_per_kilogram_kelvin> {};
+struct joule_per_mole_kelvin : derived_unit<joule_per_mole_kelvin> {};
 
 struct dim_heat_capacity :
     isq::dim_heat_capacity<dim_heat_capacity, joule_per_kelvin, dim_energy, dim_thermodynamic_temperature> {};
diff --git a/src/systems/si/include/units/isq/si/luminance.h b/src/systems/si/include/units/isq/si/luminance.h
index d6c6b74f..48f01073 100644
--- a/src/systems/si/include/units/isq/si/luminance.h
+++ b/src/systems/si/include/units/isq/si/luminance.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct candela_per_metre_sq : unit<candela_per_metre_sq> {};
+struct candela_per_metre_sq : derived_unit<candela_per_metre_sq> {};
 struct dim_luminance : isq::dim_luminance<dim_luminance, candela_per_metre_sq, dim_luminous_intensity, dim_length> {};
 
 template<UnitOf<dim_luminance> U, Representation Rep = double>
diff --git a/src/systems/si/include/units/isq/si/molar_energy.h b/src/systems/si/include/units/isq/si/molar_energy.h
index fa4cae49..02cb9072 100644
--- a/src/systems/si/include/units/isq/si/molar_energy.h
+++ b/src/systems/si/include/units/isq/si/molar_energy.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct joule_per_mole : unit<joule_per_mole> {};
+struct joule_per_mole : derived_unit<joule_per_mole> {};
 
 struct dim_molar_energy :
     isq::dim_molar_energy<dim_molar_energy, joule_per_mole, dim_energy, dim_amount_of_substance> {};
diff --git a/src/systems/si/include/units/isq/si/momentum.h b/src/systems/si/include/units/isq/si/momentum.h
index f4605e88..46446c92 100644
--- a/src/systems/si/include/units/isq/si/momentum.h
+++ b/src/systems/si/include/units/isq/si/momentum.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct kilogram_metre_per_second : unit<kilogram_metre_per_second> {};
+struct kilogram_metre_per_second : derived_unit<kilogram_metre_per_second> {};
 struct dim_momentum : isq::dim_momentum<dim_momentum, kilogram_metre_per_second, dim_mass, dim_speed> {};
 
 template<UnitOf<dim_momentum> U, Representation Rep = double>
diff --git a/src/systems/si/include/units/isq/si/permeability.h b/src/systems/si/include/units/isq/si/permeability.h
index 2cb04734..5b961b21 100644
--- a/src/systems/si/include/units/isq/si/permeability.h
+++ b/src/systems/si/include/units/isq/si/permeability.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct henry_per_metre : unit<henry_per_metre> {};
+struct henry_per_metre : derived_unit<henry_per_metre> {};
 
 struct dim_permeability : isq::dim_permeability<dim_permeability, henry_per_metre, dim_inductance, dim_length> {};
 
diff --git a/src/systems/si/include/units/isq/si/permittivity.h b/src/systems/si/include/units/isq/si/permittivity.h
index bb6b1953..cd99be6c 100644
--- a/src/systems/si/include/units/isq/si/permittivity.h
+++ b/src/systems/si/include/units/isq/si/permittivity.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct farad_per_metre : unit<farad_per_metre> {};
+struct farad_per_metre : derived_unit<farad_per_metre> {};
 
 struct dim_permittivity : isq::dim_permittivity<dim_permittivity, farad_per_metre, dim_capacitance, dim_length> {};
 
diff --git a/src/systems/si/include/units/isq/si/speed.h b/src/systems/si/include/units/isq/si/speed.h
index ddb022cd..a2c3adc0 100644
--- a/src/systems/si/include/units/isq/si/speed.h
+++ b/src/systems/si/include/units/isq/si/speed.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct metre_per_second : unit<metre_per_second> {};
+struct metre_per_second : derived_unit<metre_per_second> {};
 struct dim_speed : isq::dim_speed<dim_speed, metre_per_second, dim_length, dim_time> {};
 
 struct kilometre_per_hour : derived_deduced_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
diff --git a/src/systems/si/include/units/isq/si/surface_tension.h b/src/systems/si/include/units/isq/si/surface_tension.h
index 87b02a2c..382b133f 100644
--- a/src/systems/si/include/units/isq/si/surface_tension.h
+++ b/src/systems/si/include/units/isq/si/surface_tension.h
@@ -33,7 +33,7 @@
 
 namespace units::isq::si {
 
-struct newton_per_metre : unit<newton_per_metre> {};
+struct newton_per_metre : derived_unit<newton_per_metre> {};
 
 struct dim_surface_tension : isq::dim_surface_tension<dim_surface_tension, newton_per_metre, dim_force, dim_length> {};
 
diff --git a/src/systems/si/include/units/isq/si/thermal_conductivity.h b/src/systems/si/include/units/isq/si/thermal_conductivity.h
index d4a09c9f..64177b52 100644
--- a/src/systems/si/include/units/isq/si/thermal_conductivity.h
+++ b/src/systems/si/include/units/isq/si/thermal_conductivity.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct watt_per_metre_kelvin : unit<watt_per_metre_kelvin> {};
+struct watt_per_metre_kelvin : derived_unit<watt_per_metre_kelvin> {};
 
 struct dim_thermal_conductivity :
     isq::dim_thermal_conductivity<dim_thermal_conductivity, watt_per_metre_kelvin, dim_power, dim_length,
diff --git a/src/systems/si/include/units/isq/si/torque.h b/src/systems/si/include/units/isq/si/torque.h
index 1245cf6c..14e5aec2 100644
--- a/src/systems/si/include/units/isq/si/torque.h
+++ b/src/systems/si/include/units/isq/si/torque.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct newton_metre_per_radian : unit<newton_metre_per_radian> {};
+struct newton_metre_per_radian : derived_unit<newton_metre_per_radian> {};
 
 struct dim_torque : isq::dim_torque<dim_torque, newton_metre_per_radian, dim_force, dim_length, dim_angle<>> {};
 
diff --git a/src/systems/si/include/units/isq/si/volume.h b/src/systems/si/include/units/isq/si/volume.h
index 6f0dc9b1..a1f77b6e 100644
--- a/src/systems/si/include/units/isq/si/volume.h
+++ b/src/systems/si/include/units/isq/si/volume.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct cubic_metre : unit<cubic_metre> {};
+struct cubic_metre : derived_unit<cubic_metre> {};
 struct dim_volume : isq::dim_volume<dim_volume, cubic_metre, dim_length> {};
 
 struct cubic_yoctometre : derived_deduced_unit<cubic_yoctometre, dim_volume, yoctometre> {};
diff --git a/test/unit_test/static/custom_unit_test.cpp b/test/unit_test/static/custom_unit_test.cpp
index 15216be8..bf26b340 100644
--- a/test/unit_test/static/custom_unit_test.cpp
+++ b/test/unit_test/static/custom_unit_test.cpp
@@ -36,7 +36,7 @@ using namespace units;
 using namespace units::isq::si;
 
 // power spectral density
-struct sq_volt_per_hertz : unit<sq_volt_per_hertz> {};
+struct sq_volt_per_hertz : derived_unit<sq_volt_per_hertz> {};
 struct dim_power_spectral_density :
     derived_dimension<dim_power_spectral_density, sq_volt_per_hertz, units::exponent<dim_voltage, 2>,
                       units::exponent<dim_frequency, -1>> {};
@@ -45,7 +45,7 @@ template<UnitOf<dim_power_spectral_density> U, Representation Rep = double>
 using power_spectral_density = quantity<dim_power_spectral_density, U, Rep>;
 
 // amplitude spectral density
-struct volt_per_sqrt_hertz : unit<volt_per_sqrt_hertz> {};
+struct volt_per_sqrt_hertz : derived_unit<volt_per_sqrt_hertz> {};
 struct dim_amplitude_spectral_density :
     derived_dimension<dim_amplitude_spectral_density, volt_per_sqrt_hertz, units::exponent<dim_voltage, 1>,
                       units::exponent<dim_frequency, -1, 2>> {};
@@ -69,7 +69,7 @@ static_assert(compare<decltype(sqrt(power_spectral_density<sq_volt_per_hertz>(16
 
 namespace {
 
-struct kilogram_per_second : unit<kilogram_per_second> {};
+struct kilogram_per_second : derived_unit<kilogram_per_second> {};
 struct dim_mass_rate :
     derived_dimension<dim_mass_rate, kilogram_per_second, units::exponent<dim_mass, 1>, units::exponent<dim_time, -1>> {
 };
diff --git a/test/unit_test/static/unit_test.cpp b/test/unit_test/static/unit_test.cpp
index 059ef739..ddd97b88 100644
--- a/test/unit_test/static/unit_test.cpp
+++ b/test/unit_test/static/unit_test.cpp
@@ -52,7 +52,7 @@ static_assert([]<Prefix P>(P) {
 }(si::kilo{}));  // no prefix allowed
 #endif
 
-struct metre_per_second : unit<metre_per_second> {};
+struct metre_per_second : derived_unit<metre_per_second> {};
 struct dim_speed :
     derived_dimension<dim_speed, metre_per_second, units::exponent<dim_length, 1>, units::exponent<dim_time, -1>> {};
 struct kilometre_per_hour : derived_deduced_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};

From 725d193122727dd5ab5ef94f0d7ddfc46f6c0789 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 11:49:14 +0200
Subject: [PATCH 44/68] refactor: :boom: ! `U::is_named` removed from the unit
 types and replaced with `NamedUnit` concept

---
 src/core/include/units/base_dimension.h      |  3 +-
 src/core/include/units/bits/basic_concepts.h | 13 +++++-
 src/core/include/units/bits/unit_text.h      |  2 +-
 src/core/include/units/unit.h                | 42 +++++++++++++-------
 4 files changed, 41 insertions(+), 19 deletions(-)

diff --git a/src/core/include/units/base_dimension.h b/src/core/include/units/base_dimension.h
index 14421e25..7515d97b 100644
--- a/src/core/include/units/base_dimension.h
+++ b/src/core/include/units/base_dimension.h
@@ -50,8 +50,7 @@ namespace units {
  * @tparam Symbol an unique identifier of the base dimension used to provide dimensional analysis support
  * @tparam U a base unit to be used for this base dimension
  */
-template<basic_fixed_string Symbol, Unit U>
-  requires U::is_named
+template<basic_fixed_string Symbol, NamedUnit U>
 struct base_dimension {
   static constexpr auto symbol = Symbol;  ///< Unique base dimension identifier
   using base_unit = U;                    ///< Base unit adopted for this dimension
diff --git a/src/core/include/units/bits/basic_concepts.h b/src/core/include/units/bits/basic_concepts.h
index ecff7a2f..617fec05 100644
--- a/src/core/include/units/bits/basic_concepts.h
+++ b/src/core/include/units/bits/basic_concepts.h
@@ -96,9 +96,18 @@ void to_base_scaled_unit(const volatile scaled_unit<R, U>*);
 template<typename T>
 concept Unit = requires(T* t) { detail::to_base_scaled_unit(t); };
 
+namespace detail {
+
+template<typename>
+inline constexpr bool is_named = false;
+
+}
+
+template<typename T>
+concept NamedUnit = Unit<T> && detail::is_named<T>;
+
 // BaseDimension
-template<basic_fixed_string Symbol, Unit U>
-  requires U::is_named
+template<basic_fixed_string Symbol, NamedUnit U>
 struct base_dimension;
 
 namespace detail {
diff --git a/src/core/include/units/bits/unit_text.h b/src/core/include/units/bits/unit_text.h
index ec6675bc..917c7f86 100644
--- a/src/core/include/units/bits/unit_text.h
+++ b/src/core/include/units/bits/unit_text.h
@@ -110,7 +110,7 @@ template<Exponent Exp>
 constexpr auto exponent_list_with_named_units(Exp)
 {
   using dim = TYPENAME Exp::dimension;
-  if constexpr (dimension_unit<dim>::is_named) {
+  if constexpr (NamedUnit<dimension_unit<dim>>) {
     return exponent_list<Exp>();
   } else {
     using recipe = TYPENAME dim::recipe;
diff --git a/src/core/include/units/unit.h b/src/core/include/units/unit.h
index f2faf55d..483826b4 100644
--- a/src/core/include/units/unit.h
+++ b/src/core/include/units/unit.h
@@ -79,7 +79,6 @@ struct same_unit_reference : is_same<typename U1::reference, typename U2::refere
  */
 template<typename Child, basic_symbol_text Symbol, PrefixFamily PF>
 struct named_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {
-  static constexpr bool is_named = true;
   static constexpr auto symbol = Symbol;
   using prefix_family = PF;
 };
@@ -101,7 +100,6 @@ struct named_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {
 template<typename Child, basic_symbol_text Symbol, PrefixFamily PF, ratio R, Unit U>
   requires UnitRatio<R>
 struct named_scaled_unit : downcast_dispatch<Child, scaled_unit<R * U::ratio, typename U::reference>> {
-  static constexpr bool is_named = true;
   static constexpr auto symbol = Symbol;
   using prefix_family = PF;
 };
@@ -117,10 +115,9 @@ struct named_scaled_unit : downcast_dispatch<Child, scaled_unit<R * U::ratio, ty
  * @tparam P prefix to be appied to the reference unit
  * @tparam U reference unit
  */
-template<typename Child, Prefix P, Unit U>
-  requires U::is_named && std::same_as<typename P::prefix_family, typename U::prefix_family>
+template<typename Child, Prefix P, NamedUnit U>
+  requires std::same_as<typename P::prefix_family, typename U::prefix_family>
 struct prefixed_unit : downcast_dispatch<Child, scaled_unit<P::ratio * U::ratio, typename U::reference>> {
-  static constexpr bool is_named = true;
   static constexpr auto symbol = P::symbol + U::symbol;
   using prefix_family = no_prefix;
 };
@@ -135,7 +132,6 @@ struct prefixed_unit : downcast_dispatch<Child, scaled_unit<P::ratio * U::ratio,
  */
 template<typename Child>
 struct derived_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {
-  static constexpr bool is_named = false;
   using prefix_family = no_prefix;
 };
 
@@ -152,11 +148,9 @@ struct derived_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {
  * @tparam U the unit of the first composite dimension from provided derived dimension's recipe
  * @tparam URest the units for the rest of dimensions from the recipe
  */
-template<typename Child, DerivedDimension Dim, Unit U, Unit... URest>
-  requires detail::same_scaled_units<typename Dim::recipe, U, URest...> &&
-           (U::is_named && (URest::is_named && ... && true))
+template<typename Child, DerivedDimension Dim, NamedUnit U, NamedUnit... URest>
+  requires detail::same_scaled_units<typename Dim::recipe, U, URest...>
 struct derived_deduced_unit : downcast_dispatch<Child, detail::derived_deduced_unit<Dim, U, URest...>> {
-  static constexpr bool is_named = false;
   static constexpr auto symbol = detail::derived_symbol_text<Dim, U, URest...>();
   using prefix_family = no_prefix;
 };
@@ -176,7 +170,6 @@ struct derived_deduced_unit : downcast_dispatch<Child, detail::derived_deduced_u
  */
 template<Unit U, basic_symbol_text Symbol, PrefixFamily PF>
 struct alias_unit : U {
-  static constexpr bool is_named = true;
   static constexpr auto symbol = Symbol;
   using prefix_family = PF;
 };
@@ -196,10 +189,9 @@ struct alias_unit : U {
 // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95015
 // template<Unit U, Prefix P, AliasUnit AU>
 //   requires (!AliasUnit<U>) && std::same_as<typename P::prefix_family, typename AU::prefix_family>
-template<Unit U, Prefix P, Unit AU>
-  requires AU::is_named && std::same_as<typename P::prefix_family, typename AU::prefix_family>
+template<Unit U, Prefix P, NamedUnit AU>
+  requires std::same_as<typename P::prefix_family, typename AU::prefix_family>
 struct prefixed_alias_unit : U {
-  static constexpr bool is_named = true;
   static constexpr auto symbol = P::symbol + AU::symbol;
   using prefix_family = no_prefix;
 };
@@ -211,4 +203,26 @@ struct prefixed_alias_unit : U {
  */
 struct unknown_coherent_unit : derived_unit<unknown_coherent_unit> {};
 
+namespace detail {
+
+template<typename Child, basic_symbol_text Symbol, PrefixFamily PF>
+void is_named_impl(const volatile named_unit<Child, Symbol, PF>*);
+
+template<typename Child, basic_symbol_text Symbol, PrefixFamily PF, ratio R, Unit U>
+void is_named_impl(const volatile named_scaled_unit<Child, Symbol, PF, R, U>*);
+
+template<typename Child, typename P, typename U>
+void is_named_impl(const volatile prefixed_unit<Child, P, U>*);
+
+template<Unit U, basic_symbol_text Symbol, PrefixFamily PF>
+void is_named_impl(const volatile alias_unit<U, Symbol, PF>*);
+
+template<typename U, typename P, typename AU>
+void is_named_impl(const volatile prefixed_alias_unit<U, P, AU>*);
+
+template<Unit U>
+inline constexpr bool is_named<U> = requires(U * u) { is_named_impl(u); };
+
+}  // namespace detail
+
 }  // namespace units

From 32b36fb67084176ccb4fe7293398fa0db0f0f943 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 11:59:33 +0200
Subject: [PATCH 45/68] refactor: :boom: ! `PrefixFamily` support removed

It doesn't have much sense to restrict prefixes usage for most units and in many places we were wrong to do so already.
---
 example/custom_systems.cpp                    | 10 +--
 .../kalman_filter/kalman_filter-example_6.cpp |  2 +-
 .../kalman_filter/kalman_filter-example_7.cpp |  2 +-
 .../kalman_filter/kalman_filter-example_8.cpp |  2 +-
 example/literals/custom_systems.cpp           | 10 +--
 src/core/include/units/bits/basic_concepts.h  | 17 +----
 src/core/include/units/bits/unit_text.h       | 27 ++-----
 src/core/include/units/generic/angle.h        |  2 +-
 .../include/units/generic/dimensionless.h     |  4 +-
 src/core/include/units/prefix.h               | 29 ++------
 src/core/include/units/unit.h                 | 74 ++++++++++---------
 .../units/isq/iec80000/binary_prefixes.h      | 14 ++--
 .../units/isq/iec80000/modulation_rate.h      |  2 +-
 .../units/isq/iec80000/storage_capacity.h     | 32 ++++----
 .../units/isq/iec80000/traffic_intensity.h    |  2 +-
 .../include/units/isq/natural/units.h         |  7 +-
 .../include/units/isq/si/cgs/acceleration.h   |  2 +-
 .../si-cgs/include/units/isq/si/cgs/energy.h  |  2 +-
 .../si-cgs/include/units/isq/si/cgs/force.h   |  2 +-
 .../include/units/isq/si/cgs/pressure.h       |  2 +-
 .../si-fps/include/units/isq/si/fps/force.h   |  6 +-
 .../si-fps/include/units/isq/si/fps/length.h  |  6 +-
 .../si-fps/include/units/isq/si/fps/mass.h    | 18 ++---
 .../si-fps/include/units/isq/si/fps/power.h   |  2 +-
 .../include/units/isq/si/fps/pressure.h       |  5 +-
 .../si-fps/include/units/isq/si/fps/speed.h   |  2 +-
 .../si-hep/include/units/isq/si/hep/area.h    |  2 +-
 .../si-hep/include/units/isq/si/hep/mass.h    |  9 +--
 .../include/units/isq/si/hep/momentum.h       |  3 +-
 .../si-iau/include/units/isq/si/iau/length.h  |  6 +-
 .../include/units/isq/si/imperial/length.h    |  4 +-
 .../units/isq/si/international/length.h       | 14 ++--
 .../units/isq/si/international/speed.h        |  2 +-
 .../include/units/isq/si/typographic/length.h |  8 +-
 .../include/units/isq/si/uscs/length.h        |  6 +-
 .../si/include/units/isq/si/absorbed_dose.h   |  2 +-
 .../units/isq/si/amount_of_substance.h        |  2 +-
 .../include/units/isq/si/angular_velocity.h   |  2 +-
 src/systems/si/include/units/isq/si/area.h    |  2 +-
 .../si/include/units/isq/si/capacitance.h     |  2 +-
 .../include/units/isq/si/catalytic_activity.h |  4 +-
 .../si/include/units/isq/si/conductance.h     |  2 +-
 .../si/include/units/isq/si/electric_charge.h |  2 +-
 .../include/units/isq/si/electric_current.h   |  2 +-
 src/systems/si/include/units/isq/si/energy.h  |  4 +-
 src/systems/si/include/units/isq/si/force.h   |  2 +-
 .../si/include/units/isq/si/frequency.h       |  2 +-
 .../si/include/units/isq/si/inductance.h      |  2 +-
 src/systems/si/include/units/isq/si/length.h  |  4 +-
 .../include/units/isq/si/luminous_intensity.h |  2 +-
 .../si/include/units/isq/si/magnetic_flux.h   |  2 +-
 .../include/units/isq/si/magnetic_induction.h |  4 +-
 src/systems/si/include/units/isq/si/mass.h    |  7 +-
 src/systems/si/include/units/isq/si/power.h   |  2 +-
 .../si/include/units/isq/si/prefixes.h        | 42 +++++------
 .../si/include/units/isq/si/pressure.h        |  2 +-
 .../si/include/units/isq/si/radioactivity.h   |  2 +-
 .../si/include/units/isq/si/resistance.h      |  2 +-
 .../units/isq/si/thermodynamic_temperature.h  |  2 +-
 src/systems/si/include/units/isq/si/time.h    |  8 +-
 src/systems/si/include/units/isq/si/voltage.h |  2 +-
 src/systems/si/include/units/isq/si/volume.h  |  2 +-
 test/unit_test/static/concepts_test.cpp       | 13 ++--
 test/unit_test/static/dimension_op_test.cpp   |  8 +-
 test/unit_test/static/type_list_test.cpp      |  4 +-
 test/unit_test/static/unit_test.cpp           | 14 ++--
 66 files changed, 221 insertions(+), 268 deletions(-)

diff --git a/example/custom_systems.cpp b/example/custom_systems.cpp
index f8dfd28f..8139420f 100644
--- a/example/custom_systems.cpp
+++ b/example/custom_systems.cpp
@@ -32,8 +32,8 @@ using namespace units;
 
 namespace fps {
 
-struct foot : named_unit<foot, "ft", no_prefix> {};
-struct yard : named_scaled_unit<yard, "yd", no_prefix, ratio(3), foot> {};
+struct foot : named_unit<foot, "ft"> {};
+struct yard : named_scaled_unit<yard, "yd", ratio(3), foot> {};
 
 struct dim_length : base_dimension<"L", foot> {};
 
@@ -44,7 +44,7 @@ using length = quantity<dim_length, U, Rep>;
 
 namespace si {
 
-struct metre : named_unit<metre, "m", units::isq::si::prefix> {};
+struct metre : named_unit<metre, "m"> {};
 struct kilometre : prefixed_unit<kilometre, units::isq::si::kilo, metre> {};
 
 struct dim_length : base_dimension<"L", metre> {};
@@ -54,8 +54,8 @@ using length = quantity<dim_length, U, Rep>;
 
 namespace fps {
 
-struct foot : named_scaled_unit<foot, "ft", no_prefix, ratio(3'048, 1'000, -1), metre> {};
-struct yard : named_scaled_unit<yard, "yd", no_prefix, ratio(3), foot> {};
+struct foot : named_scaled_unit<foot, "ft", ratio(3'048, 1'000, -1), metre> {};
+struct yard : named_scaled_unit<yard, "yd", ratio(3), foot> {};
 
 struct dim_length : base_dimension<"L", foot> {};
 
diff --git a/example/kalman_filter/kalman_filter-example_6.cpp b/example/kalman_filter/kalman_filter-example_6.cpp
index fac8c34b..b77d3d62 100644
--- a/example/kalman_filter/kalman_filter-example_6.cpp
+++ b/example/kalman_filter/kalman_filter-example_6.cpp
@@ -32,7 +32,7 @@
 // TODO Fix when Celsius is properly supported (#232)
 namespace units::isq::si {
 
-struct degree_celsius : alias_unit<kelvin, basic_symbol_text{"°C", "deg_C"}, no_prefix> {};
+struct degree_celsius : alias_unit<kelvin, basic_symbol_text{"°C", "deg_C"}> {};
 
 namespace thermodynamic_temperature_references {
 
diff --git a/example/kalman_filter/kalman_filter-example_7.cpp b/example/kalman_filter/kalman_filter-example_7.cpp
index 42ce7025..7387ab56 100644
--- a/example/kalman_filter/kalman_filter-example_7.cpp
+++ b/example/kalman_filter/kalman_filter-example_7.cpp
@@ -32,7 +32,7 @@
 // TODO Fix when Celsius is properly supported (#232)
 namespace units::isq::si {
 
-struct degree_celsius : alias_unit<kelvin, basic_symbol_text{"°C", "deg_C"}, no_prefix> {};
+struct degree_celsius : alias_unit<kelvin, basic_symbol_text{"°C", "deg_C"}> {};
 
 namespace thermodynamic_temperature_references {
 
diff --git a/example/kalman_filter/kalman_filter-example_8.cpp b/example/kalman_filter/kalman_filter-example_8.cpp
index 3b81ae70..c2e0e1f6 100644
--- a/example/kalman_filter/kalman_filter-example_8.cpp
+++ b/example/kalman_filter/kalman_filter-example_8.cpp
@@ -32,7 +32,7 @@
 // TODO Fix when Celsius is properly supported (#232)
 namespace units::isq::si {
 
-struct degree_celsius : alias_unit<kelvin, basic_symbol_text{"°C", "deg_C"}, no_prefix> {};
+struct degree_celsius : alias_unit<kelvin, basic_symbol_text{"°C", "deg_C"}> {};
 
 namespace thermodynamic_temperature_references {
 
diff --git a/example/literals/custom_systems.cpp b/example/literals/custom_systems.cpp
index f8fa8a3b..403475e1 100644
--- a/example/literals/custom_systems.cpp
+++ b/example/literals/custom_systems.cpp
@@ -32,8 +32,8 @@ using namespace units;
 
 namespace fps {
 
-struct foot : named_unit<foot, "ft", no_prefix> {};
-struct yard : named_scaled_unit<yard, "yd", no_prefix, ratio(3), foot> {};
+struct foot : named_unit<foot, "ft"> {};
+struct yard : named_scaled_unit<yard, "yd", ratio(3), foot> {};
 
 struct dim_length : base_dimension<"L", foot> {};
 
@@ -44,7 +44,7 @@ using length = quantity<dim_length, U, Rep>;
 
 namespace si {
 
-struct metre : named_unit<metre, "m", units::isq::si::prefix> {};
+struct metre : named_unit<metre, "m"> {};
 struct kilometre : prefixed_unit<kilometre, units::isq::si::kilo, metre> {};
 
 struct dim_length : base_dimension<"L", metre> {};
@@ -54,8 +54,8 @@ using length = quantity<dim_length, U, Rep>;
 
 namespace fps {
 
-struct foot : named_scaled_unit<foot, "ft", no_prefix, ratio(3'048, 1'000, -1), metre> {};
-struct yard : named_scaled_unit<yard, "yd", no_prefix, ratio(3), foot> {};
+struct foot : named_scaled_unit<foot, "ft", ratio(3'048, 1'000, -1), metre> {};
+struct yard : named_scaled_unit<yard, "yd", ratio(3), foot> {};
 
 struct dim_length : base_dimension<"L", foot> {};
 
diff --git a/src/core/include/units/bits/basic_concepts.h b/src/core/include/units/bits/basic_concepts.h
index 617fec05..d3daf798 100644
--- a/src/core/include/units/bits/basic_concepts.h
+++ b/src/core/include/units/bits/basic_concepts.h
@@ -37,25 +37,14 @@
 
 namespace units {
 
-// PrefixFamily
-struct prefix_family;
-
-/**
- * @brief A concept matching a prefix family
- *
- * Satisfied by all types derived from `prefix_family`
- */
-template<typename T>
-concept PrefixFamily = std::derived_from<T, prefix_family>;
-
 // Prefix
 namespace detail {
 
-template<PrefixFamily PF, ratio R>
+template<ratio R>
 struct prefix_base;
 
-template<PrefixFamily PF, ratio R>
-void to_prefix_base(const volatile prefix_base<PF, R>*);
+template<ratio R>
+void to_prefix_base(const volatile prefix_base<R>*);
 
 }  // namespace detail
 
diff --git a/src/core/include/units/bits/unit_text.h b/src/core/include/units/bits/unit_text.h
index 917c7f86..a8c323e4 100644
--- a/src/core/include/units/bits/unit_text.h
+++ b/src/core/include/units/bits/unit_text.h
@@ -57,28 +57,19 @@ constexpr auto ratio_text()
   }
 }
 
-template<ratio R, typename PrefixFamily, std::size_t SymbolLen>
+template<ratio R, std::size_t SymbolLen>
 constexpr auto prefix_or_ratio_text()
 {
   if constexpr (R.num == 1 && R.den == 1 && R.exp == 0) {
     // no ratio/prefix
     return basic_fixed_string("");
   } else {
-    if constexpr (!is_same_v<PrefixFamily, no_prefix>) {
-      // try to form a prefix
-      using prefix = downcast<detail::prefix_base<PrefixFamily, R>>;
+    // try to form a prefix
+    using prefix = downcast<detail::prefix_base<R>>;
 
-      if constexpr (!is_same_v<prefix, prefix_base<PrefixFamily, R>>) {
-        // print as a prefixed unit
-        return prefix::symbol;
-      } else {
-        // print as a ratio of the coherent unit
-        constexpr auto txt = ratio_text<R>();
-        if constexpr (SymbolLen > 0 && txt.standard().size() > 0)
-          return txt + basic_fixed_string(" ");
-        else
-          return txt;
-      }
+    if constexpr (!is_same_v<prefix, prefix_base<R>>) {
+      // print as a prefixed unit
+      return prefix::symbol;
     } else {
       // print as a ratio of the coherent unit
       constexpr auto txt = ratio_text<R>();
@@ -151,15 +142,13 @@ constexpr auto unit_text()
       // use predefined coherent unit symbol
       constexpr auto symbol_text = coherent_unit::symbol;
       constexpr auto prefix_txt =
-        prefix_or_ratio_text<U::ratio / coherent_unit::ratio, typename U::reference::prefix_family,
-                             symbol_text.standard().size()>();
+        prefix_or_ratio_text<U::ratio / coherent_unit::ratio, symbol_text.standard().size()>();
       return prefix_txt + symbol_text;
     } else {
       // use derived dimension ingredients to create a unit symbol
       constexpr auto symbol_text = derived_dimension_unit_text<Dim>();
       constexpr auto prefix_txt =
-        prefix_or_ratio_text<U::ratio / coherent_unit::ratio, typename U::reference::prefix_family,
-                             symbol_text.standard().size()>();
+        prefix_or_ratio_text<U::ratio / coherent_unit::ratio, symbol_text.standard().size()>();
       return prefix_txt + symbol_text;
     }
   }
diff --git a/src/core/include/units/generic/angle.h b/src/core/include/units/generic/angle.h
index 9aefafbb..11017a68 100644
--- a/src/core/include/units/generic/angle.h
+++ b/src/core/include/units/generic/angle.h
@@ -32,7 +32,7 @@
 
 namespace units {
 
-struct radian : named_unit<radian, "rad", isq::si::prefix> {};
+struct radian : named_unit<radian, "rad"> {};
 
 template<Unit U = radian>
 struct dim_angle : base_dimension<"A", U> {};
diff --git a/src/core/include/units/generic/dimensionless.h b/src/core/include/units/generic/dimensionless.h
index d1d34c2e..562977fc 100644
--- a/src/core/include/units/generic/dimensionless.h
+++ b/src/core/include/units/generic/dimensionless.h
@@ -30,8 +30,8 @@
 
 namespace units {
 
-struct one : named_unit<one, "", no_prefix> {};
-struct percent : named_scaled_unit<percent, "%", no_prefix, ratio(1, 100), one> {};
+struct one : named_unit<one, ""> {};
+struct percent : named_scaled_unit<percent, "%", ratio(1, 100), one> {};
 
 /**
  * @brief Dimension one
diff --git a/src/core/include/units/prefix.h b/src/core/include/units/prefix.h
index 0a9386d1..901a50bd 100644
--- a/src/core/include/units/prefix.h
+++ b/src/core/include/units/prefix.h
@@ -31,26 +31,10 @@
 
 namespace units {
 
-/**
- * @brief The base for all prefix families
- *
- * Every prefix family should inherit from this type to satisfy PrefixFamily concept.
- */
-struct prefix_family {};
-
-/**
- * @brief No prefix possible for the unit
- *
- * This is a special prefix type tag specifying that the unit can not be scaled with any kind
- * of the prefix.
- */
-struct no_prefix : prefix_family {};
-
 namespace detail {
 
-template<PrefixFamily PF, ratio R>
-struct prefix_base : downcast_base<prefix_base<PF, R>> {
-  using prefix_family = PF;
+template<ratio R>
+struct prefix_base : downcast_base<prefix_base<R>> {
   static constexpr ::units::ratio ratio = R;
 };
 
@@ -63,17 +47,14 @@ struct prefix_base : downcast_base<prefix_base<PF, R>> {
  * - when defining a prefixed_unit its ratio is used to scale the reference unit and its
  *   symbol is used to prepend to the symbol of referenced unit
  * - when printing the symbol of a scaled unit that was not predefined by the user but its
- *   factor matches ratio of a prefix from the specified prefix family, its symbol will be
- *   prepended to the symbol of the unit
+ *   factor matches ratio of a prefix, its symbol will be prepended to the symbol of the unit
  *
  * @tparam Child inherited class type used by the downcasting facility (CRTP Idiom)
- * @tparam PF a type of prefix family
  * @tparam Symbol a text representation of the prefix
  * @tparam R factor to be used to scale a unit
  */
-template<typename Child, PrefixFamily PF, basic_symbol_text Symbol, ratio R>
-  requires(!std::same_as<PF, no_prefix>)
-struct prefix : downcast_dispatch<Child, detail::prefix_base<PF, R>, downcast_mode::on> {
+template<typename Child, basic_symbol_text Symbol, ratio R>
+struct prefix : downcast_dispatch<Child, detail::prefix_base<R>, downcast_mode::on> {
   static constexpr auto symbol = Symbol;
 };
 
diff --git a/src/core/include/units/unit.h b/src/core/include/units/unit.h
index 483826b4..386e360e 100644
--- a/src/core/include/units/unit.h
+++ b/src/core/include/units/unit.h
@@ -35,6 +35,13 @@
 
 namespace units {
 
+namespace detail {
+
+template<typename>
+inline constexpr bool can_be_prefixed = false;
+
+}  // namespace detail
+
 /**
  * @brief A common point for a hierarchy of units
  *
@@ -69,39 +76,31 @@ struct same_unit_reference : is_same<typename U1::reference, typename U2::refere
  * @brief A named unit
  *
  * Defines a named (in most cases coherent) unit that is then passed to a dimension definition.
- * A named unit may be used by other units defined with the prefix of the same type, unless
- * no_prefix is provided for PF template parameter (in such a case it is impossible to define
- * a prefix unit based on this one).
+ * A named unit may be composed with a prefix to create a prefixed_unit.
  *
  * @tparam Child inherited class type used by the downcasting facility (CRTP Idiom)
  * @tparam Symbol a short text representation of the unit
- * @tparam PF no_prefix or a type of prefix family
  */
-template<typename Child, basic_symbol_text Symbol, PrefixFamily PF>
+template<typename Child, basic_symbol_text Symbol>
 struct named_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {
   static constexpr auto symbol = Symbol;
-  using prefix_family = PF;
 };
 
 /**
- * @brief A scaled unit
+ * @brief A named scaled unit
  *
- * Defines a new named unit that is a scaled version of another unit. Such unit can be used by
- * other units defined with the prefix of the same type, unless no_prefix is provided for PF
- * template parameter (in such a case it is impossible to define a prefix unit based on this
- * one).
+ * Defines a new named unit that is a scaled version of another unit.
+ * A named unit may be composed with a prefix to create a prefixed_unit.
  *
  * @tparam Child inherited class type used by the downcasting facility (CRTP Idiom)
  * @tparam Symbol a short text representation of the unit
- * @tparam PF no_prefix or a type of prefix family
  * @tparam R a scale to apply to U
  * @tparam U a reference unit to scale
  */
-template<typename Child, basic_symbol_text Symbol, PrefixFamily PF, ratio R, Unit U>
+template<typename Child, basic_symbol_text Symbol, ratio R, Unit U>
   requires UnitRatio<R>
 struct named_scaled_unit : downcast_dispatch<Child, scaled_unit<R * U::ratio, typename U::reference>> {
   static constexpr auto symbol = Symbol;
-  using prefix_family = PF;
 };
 
 /**
@@ -116,10 +115,9 @@ struct named_scaled_unit : downcast_dispatch<Child, scaled_unit<R * U::ratio, ty
  * @tparam U reference unit
  */
 template<typename Child, Prefix P, NamedUnit U>
-  requires std::same_as<typename P::prefix_family, typename U::prefix_family>
+  requires detail::can_be_prefixed<U>
 struct prefixed_unit : downcast_dispatch<Child, scaled_unit<P::ratio * U::ratio, typename U::reference>> {
   static constexpr auto symbol = P::symbol + U::symbol;
-  using prefix_family = no_prefix;
 };
 
 /**
@@ -131,9 +129,7 @@ struct prefixed_unit : downcast_dispatch<Child, scaled_unit<P::ratio * U::ratio,
  * @tparam Child inherited class type used by the downcasting facility (CRTP Idiom)
  */
 template<typename Child>
-struct derived_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {
-  using prefix_family = no_prefix;
-};
+struct derived_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {};
 
 /**
  * @brief A unit with a deduced ratio and symbol
@@ -152,7 +148,6 @@ template<typename Child, DerivedDimension Dim, NamedUnit U, NamedUnit... URest>
   requires detail::same_scaled_units<typename Dim::recipe, U, URest...>
 struct derived_deduced_unit : downcast_dispatch<Child, detail::derived_deduced_unit<Dim, U, URest...>> {
   static constexpr auto symbol = detail::derived_symbol_text<Dim, U, URest...>();
-  using prefix_family = no_prefix;
 };
 
 /**
@@ -160,18 +155,14 @@ struct derived_deduced_unit : downcast_dispatch<Child, detail::derived_deduced_u
  *
  * Defines a named alias for another unit. It is useful to assign alternative names and symbols
  * to the already predefined units (i.e. "tonne" for "megagram").
- * An alias unit may be used by other units defined with the prefix of the same type, unless
- * no_prefix is provided for PF template parameter (in such a case it is impossible to define
- * a prefix unit based on this one).
+ * A alias unit may be composed with a prefix to create a prefixed_alias_unit.
  *
  * @tparam U Unit for which an alias is defined
  * @tparam Symbol a short text representation of the unit
- * @tparam PF no_prefix or a type of prefix family
  */
-template<Unit U, basic_symbol_text Symbol, PrefixFamily PF>
+template<Unit U, basic_symbol_text Symbol>
 struct alias_unit : U {
   static constexpr auto symbol = Symbol;
-  using prefix_family = PF;
 };
 
 /**
@@ -188,16 +179,15 @@ struct alias_unit : U {
 // TODO gcc bug: 95015
 // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95015
 // template<Unit U, Prefix P, AliasUnit AU>
-//   requires (!AliasUnit<U>) && std::same_as<typename P::prefix_family, typename AU::prefix_family>
+//   requires (!AliasUnit<U>)
 template<Unit U, Prefix P, NamedUnit AU>
-  requires std::same_as<typename P::prefix_family, typename AU::prefix_family>
+  requires detail::can_be_prefixed<AU>
 struct prefixed_alias_unit : U {
   static constexpr auto symbol = P::symbol + AU::symbol;
-  using prefix_family = no_prefix;
 };
 
 /**
- * @brief Unknown unit
+ * @brief Unknown coherent unit
  *
  * Used as a coherent unit of an unknown dimension.
  */
@@ -205,17 +195,17 @@ struct unknown_coherent_unit : derived_unit<unknown_coherent_unit> {};
 
 namespace detail {
 
-template<typename Child, basic_symbol_text Symbol, PrefixFamily PF>
-void is_named_impl(const volatile named_unit<Child, Symbol, PF>*);
+template<typename Child, basic_symbol_text Symbol>
+void is_named_impl(const volatile named_unit<Child, Symbol>*);
 
-template<typename Child, basic_symbol_text Symbol, PrefixFamily PF, ratio R, Unit U>
-void is_named_impl(const volatile named_scaled_unit<Child, Symbol, PF, R, U>*);
+template<typename Child, basic_symbol_text Symbol, ratio R, typename U>
+void is_named_impl(const volatile named_scaled_unit<Child, Symbol, R, U>*);
 
 template<typename Child, typename P, typename U>
 void is_named_impl(const volatile prefixed_unit<Child, P, U>*);
 
-template<Unit U, basic_symbol_text Symbol, PrefixFamily PF>
-void is_named_impl(const volatile alias_unit<U, Symbol, PF>*);
+template<typename U, basic_symbol_text Symbol>
+void is_named_impl(const volatile alias_unit<U, Symbol>*);
 
 template<typename U, typename P, typename AU>
 void is_named_impl(const volatile prefixed_alias_unit<U, P, AU>*);
@@ -223,6 +213,18 @@ void is_named_impl(const volatile prefixed_alias_unit<U, P, AU>*);
 template<Unit U>
 inline constexpr bool is_named<U> = requires(U * u) { is_named_impl(u); };
 
+template<typename Child, basic_symbol_text Symbol>
+void can_be_prefixed_impl(const volatile named_unit<Child, Symbol>*);
+
+template<typename Child, basic_symbol_text Symbol, ratio R, typename U>
+void can_be_prefixed_impl(const volatile named_scaled_unit<Child, Symbol, R, U>*);
+
+template<typename U, basic_symbol_text Symbol>
+void can_be_prefixed_impl(const volatile alias_unit<U, Symbol>*);
+
+template<Unit U>
+inline constexpr bool can_be_prefixed<U> = requires(U * u) { can_be_prefixed_impl(u); };
+
 }  // namespace detail
 
 }  // namespace units
diff --git a/src/systems/isq-iec80000/include/units/isq/iec80000/binary_prefixes.h b/src/systems/isq-iec80000/include/units/isq/iec80000/binary_prefixes.h
index e842cf3e..1ff0679e 100644
--- a/src/systems/isq-iec80000/include/units/isq/iec80000/binary_prefixes.h
+++ b/src/systems/isq-iec80000/include/units/isq/iec80000/binary_prefixes.h
@@ -26,13 +26,11 @@
 
 namespace units::isq::iec80000 {
 
-struct binary_prefix : prefix_family {};
-
-struct kibi : units::prefix<kibi, binary_prefix, "Ki", ratio(1'024)> {};
-struct mebi : units::prefix<mebi, binary_prefix, "Mi", ratio(1'048'576)> {};
-struct gibi : units::prefix<gibi, binary_prefix, "Gi", ratio(1'073'741'824)> {};
-struct tebi : units::prefix<tebi, binary_prefix, "Ti", ratio(1'099'511'627'776)> {};
-struct pebi : units::prefix<pebi, binary_prefix, "Pi", ratio(1'125'899'906'842'624)> {};
-struct exbi : units::prefix<exbi, binary_prefix, "Ei", ratio(1'152'921'504'606'846'976)> {};
+struct kibi : units::prefix<kibi, "Ki", ratio(1'024)> {};
+struct mebi : units::prefix<mebi, "Mi", ratio(1'048'576)> {};
+struct gibi : units::prefix<gibi, "Gi", ratio(1'073'741'824)> {};
+struct tebi : units::prefix<tebi, "Ti", ratio(1'099'511'627'776)> {};
+struct pebi : units::prefix<pebi, "Pi", ratio(1'125'899'906'842'624)> {};
+struct exbi : units::prefix<exbi, "Ei", ratio(1'152'921'504'606'846'976)> {};
 
 }  // namespace units::isq::iec80000
diff --git a/src/systems/isq-iec80000/include/units/isq/iec80000/modulation_rate.h b/src/systems/isq-iec80000/include/units/isq/iec80000/modulation_rate.h
index dcb3d805..40bf6d24 100644
--- a/src/systems/isq-iec80000/include/units/isq/iec80000/modulation_rate.h
+++ b/src/systems/isq-iec80000/include/units/isq/iec80000/modulation_rate.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::iec80000 {
 
-struct baud : alias_unit<si::hertz, "Bd", si::prefix> {};
+struct baud : alias_unit<si::hertz, "Bd"> {};
 struct kilobaud : prefixed_alias_unit<si::kilohertz, si::kilo, baud> {};
 struct megabaud : prefixed_alias_unit<si::megahertz, si::mega, baud> {};
 struct gigabaud : prefixed_alias_unit<si::gigahertz, si::giga, baud> {};
diff --git a/src/systems/isq-iec80000/include/units/isq/iec80000/storage_capacity.h b/src/systems/isq-iec80000/include/units/isq/iec80000/storage_capacity.h
index c8ea04f7..f88b5710 100644
--- a/src/systems/isq-iec80000/include/units/isq/iec80000/storage_capacity.h
+++ b/src/systems/isq-iec80000/include/units/isq/iec80000/storage_capacity.h
@@ -35,7 +35,8 @@
 
 namespace units::isq::iec80000 {
 
-struct bit : named_unit<bit, "bit", si::prefix> {};
+struct bit : named_unit<bit, "bit"> {};
+
 struct kilobit : prefixed_unit<kilobit, si::kilo, bit> {};
 struct megabit : prefixed_unit<megabit, si::mega, bit> {};
 struct gigabit : prefixed_unit<gigabit, si::giga, bit> {};
@@ -45,15 +46,15 @@ struct exabit : prefixed_unit<exabit, si::exa, bit> {};
 struct zettabit : prefixed_unit<zettabit, si::zetta, bit> {};
 struct yottabit : prefixed_unit<yottabit, si::yotta, bit> {};
 
-struct binary_prefix_bit : alias_unit<bit, "bit", binary_prefix> {};
-struct kibibit : prefixed_unit<kibibit, kibi, binary_prefix_bit> {};
-struct mebibit : prefixed_unit<mebibit, mebi, binary_prefix_bit> {};
-struct gibibit : prefixed_unit<gibibit, gibi, binary_prefix_bit> {};
-struct tebibit : prefixed_unit<tebibit, tebi, binary_prefix_bit> {};
-struct pebibit : prefixed_unit<pebibit, pebi, binary_prefix_bit> {};
-struct exbibit : prefixed_unit<exbibit, exbi, binary_prefix_bit> {};
+struct kibibit : prefixed_unit<kibibit, kibi, bit> {};
+struct mebibit : prefixed_unit<mebibit, mebi, bit> {};
+struct gibibit : prefixed_unit<gibibit, gibi, bit> {};
+struct tebibit : prefixed_unit<tebibit, tebi, bit> {};
+struct pebibit : prefixed_unit<pebibit, pebi, bit> {};
+struct exbibit : prefixed_unit<exbibit, exbi, bit> {};
+
+struct byte : named_scaled_unit<byte, "B", ratio(8), bit> {};
 
-struct byte : named_scaled_unit<byte, "B", si::prefix, ratio(8), bit> {};
 struct kilobyte : prefixed_unit<kilobyte, si::kilo, byte> {};
 struct megabyte : prefixed_unit<megabyte, si::mega, byte> {};
 struct gigabyte : prefixed_unit<gigabyte, si::giga, byte> {};
@@ -63,13 +64,12 @@ struct exabyte : prefixed_unit<exabyte, si::exa, byte> {};
 struct zettabyte : prefixed_unit<zettabyte, si::zetta, byte> {};
 struct yottabyte : prefixed_unit<yottabyte, si::yotta, byte> {};
 
-struct binary_prefix_byte : alias_unit<byte, "B", binary_prefix> {};
-struct kibibyte : prefixed_unit<kibibyte, kibi, binary_prefix_byte> {};
-struct mebibyte : prefixed_unit<mebibyte, mebi, binary_prefix_byte> {};
-struct gibibyte : prefixed_unit<gibibyte, gibi, binary_prefix_byte> {};
-struct tebibyte : prefixed_unit<tebibyte, tebi, binary_prefix_byte> {};
-struct pebibyte : prefixed_unit<pebibyte, pebi, binary_prefix_byte> {};
-// struct exbibyte : prefixed_unit<exbibyte, exbi, binary_prefix_byte> {};
+struct kibibyte : prefixed_unit<kibibyte, kibi, byte> {};
+struct mebibyte : prefixed_unit<mebibyte, mebi, byte> {};
+struct gibibyte : prefixed_unit<gibibyte, gibi, byte> {};
+struct tebibyte : prefixed_unit<tebibyte, tebi, byte> {};
+struct pebibyte : prefixed_unit<pebibyte, pebi, byte> {};
+// struct exbibyte : prefixed_unit<exbibyte, exbi, byte> {};
 
 struct dim_storage_capacity : base_dimension<"M", byte> {};
 
diff --git a/src/systems/isq-iec80000/include/units/isq/iec80000/traffic_intensity.h b/src/systems/isq-iec80000/include/units/isq/iec80000/traffic_intensity.h
index 3c17f62d..03a31646 100644
--- a/src/systems/isq-iec80000/include/units/isq/iec80000/traffic_intensity.h
+++ b/src/systems/isq-iec80000/include/units/isq/iec80000/traffic_intensity.h
@@ -33,7 +33,7 @@
 
 namespace units::isq::iec80000 {
 
-struct erlang : named_unit<erlang, "E", no_prefix> {};
+struct erlang : named_unit<erlang, "E"> {};
 
 struct dim_traffic_intensity : base_dimension<"A", erlang> {};
 
diff --git a/src/systems/isq-natural/include/units/isq/natural/units.h b/src/systems/isq-natural/include/units/isq/natural/units.h
index 1d64e28b..82712296 100644
--- a/src/systems/isq-natural/include/units/isq/natural/units.h
+++ b/src/systems/isq-natural/include/units/isq/natural/units.h
@@ -31,11 +31,10 @@
 
 namespace units::isq::natural {
 
-struct electronvolt : named_unit<electronvolt, "eV", si::prefix> {};
+struct electronvolt : named_unit<electronvolt, "eV"> {};
 struct gigaelectronvolt : prefixed_unit<gigaelectronvolt, si::giga, electronvolt> {};
-struct inverted_gigaelectronvolt :
-    named_unit<inverted_gigaelectronvolt, basic_symbol_text{"GeV⁻¹", "GeV^-1"}, no_prefix> {};
-struct square_gigaelectronvolt : named_unit<square_gigaelectronvolt, basic_symbol_text{"GeV²", "GeV^2"}, no_prefix> {};
+struct inverted_gigaelectronvolt : named_unit<inverted_gigaelectronvolt, basic_symbol_text{"GeV⁻¹", "GeV^-1"}> {};
+struct square_gigaelectronvolt : named_unit<square_gigaelectronvolt, basic_symbol_text{"GeV²", "GeV^2"}> {};
 
 // NOTE: eV as a base unit with no relation to joule prevents us from going back
 // from natural units to SI. Do we need such a support or should we treat
diff --git a/src/systems/si-cgs/include/units/isq/si/cgs/acceleration.h b/src/systems/si-cgs/include/units/isq/si/cgs/acceleration.h
index 53d56784..fc983980 100644
--- a/src/systems/si-cgs/include/units/isq/si/cgs/acceleration.h
+++ b/src/systems/si-cgs/include/units/isq/si/cgs/acceleration.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si::cgs {
 
-struct gal : named_unit<gal, "Gal", si::prefix> {};
+struct gal : named_unit<gal, "Gal"> {};
 struct dim_acceleration : isq::dim_acceleration<dim_acceleration, gal, dim_length, dim_time> {};
 
 template<UnitOf<dim_acceleration> U, Representation Rep = double>
diff --git a/src/systems/si-cgs/include/units/isq/si/cgs/energy.h b/src/systems/si-cgs/include/units/isq/si/cgs/energy.h
index d6e0c16b..7ca8af7f 100644
--- a/src/systems/si-cgs/include/units/isq/si/cgs/energy.h
+++ b/src/systems/si-cgs/include/units/isq/si/cgs/energy.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si::cgs {
 
-struct erg : named_unit<erg, "erg", si::prefix> {};
+struct erg : named_unit<erg, "erg"> {};
 
 struct dim_energy : isq::dim_energy<dim_energy, erg, dim_force, dim_length> {};
 
diff --git a/src/systems/si-cgs/include/units/isq/si/cgs/force.h b/src/systems/si-cgs/include/units/isq/si/cgs/force.h
index e00f5a0d..f6f7bca3 100644
--- a/src/systems/si-cgs/include/units/isq/si/cgs/force.h
+++ b/src/systems/si-cgs/include/units/isq/si/cgs/force.h
@@ -36,7 +36,7 @@
 
 namespace units::isq::si::cgs {
 
-struct dyne : named_unit<dyne, "dyn", si::prefix> {};
+struct dyne : named_unit<dyne, "dyn"> {};
 
 struct dim_force : isq::dim_force<dim_force, dyne, dim_mass, dim_acceleration> {};
 
diff --git a/src/systems/si-cgs/include/units/isq/si/cgs/pressure.h b/src/systems/si-cgs/include/units/isq/si/cgs/pressure.h
index 5d4f89ea..e3b1a36a 100644
--- a/src/systems/si-cgs/include/units/isq/si/cgs/pressure.h
+++ b/src/systems/si-cgs/include/units/isq/si/cgs/pressure.h
@@ -36,7 +36,7 @@
 
 namespace units::isq::si::cgs {
 
-struct barye : named_unit<barye, "Ba", si::prefix> {};
+struct barye : named_unit<barye, "Ba"> {};
 
 struct dim_pressure : isq::dim_pressure<dim_pressure, barye, dim_force, dim_area> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/force.h b/src/systems/si-fps/include/units/isq/si/fps/force.h
index 8958ca44..19f52527 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/force.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/force.h
@@ -37,15 +37,15 @@
 namespace units::isq::si::fps {
 
 // https://en.wikipedia.org/wiki/Poundal
-struct poundal : named_unit<poundal, "pdl", no_prefix> {};
+struct poundal : named_unit<poundal, "pdl"> {};
 
 // https://en.wikipedia.org/wiki/Pound_(force)
-struct pound_force : named_scaled_unit<pound_force, "lbf", si::prefix, ratio(32'174'049, 1'000'000), poundal> {};
+struct pound_force : named_scaled_unit<pound_force, "lbf", ratio(32'174'049, 1'000'000), poundal> {};
 
 struct kilopound_force : prefixed_unit<kilopound_force, si::kilo, pound_force> {};
 
 // https://en.wikipedia.org/wiki/Kip_(unit),
-struct kip : alias_unit<kilopound_force, "klbf", no_prefix> {};
+struct kip : alias_unit<kilopound_force, "klbf"> {};
 
 struct dim_force : isq::dim_force<dim_force, poundal, dim_mass, dim_acceleration> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/length.h b/src/systems/si-fps/include/units/isq/si/fps/length.h
index c33819cd..8f307136 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/length.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/length.h
@@ -43,13 +43,13 @@ using si::international::thou;
 using si::international::yard;
 
 // thousandth of an inch
-struct thousandth : alias_unit<thou, "thou", no_prefix> {};
+struct thousandth : alias_unit<thou, "thou"> {};
 
 struct kiloyard : prefixed_unit<kiloyard, si::kilo, yard> {};
 
-struct mile : named_scaled_unit<mile, "mile", no_prefix, ratio(5'280), foot> {};
+struct mile : named_scaled_unit<mile, "mile", ratio(5'280), foot> {};
 
-struct nautical_mile : named_scaled_unit<nautical_mile, "nmi", no_prefix, ratio(2'000), yard> {};
+struct nautical_mile : named_scaled_unit<nautical_mile, "nmi", ratio(2'000), yard> {};
 
 struct dim_length : isq::dim_length<foot> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/mass.h b/src/systems/si-fps/include/units/isq/si/fps/mass.h
index 559593d0..2891c8bc 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/mass.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/mass.h
@@ -35,28 +35,28 @@
 namespace units::isq::si::fps {
 
 // https://en.wikipedia.org/wiki/Pound_(mass)
-struct pound : named_scaled_unit<pound, "lb", no_prefix, ratio(45'359'237, 100'000'000), si::kilogram> {};
+struct pound : named_scaled_unit<pound, "lb", ratio(45'359'237, 100'000'000), si::kilogram> {};
 
 struct dim_mass : isq::dim_mass<pound> {};
 
 template<UnitOf<dim_mass> U, Representation Rep = double>
 using mass = quantity<dim_mass, U, Rep>;
 
-struct grain : named_scaled_unit<grain, "gr", no_prefix, ratio(1, 7000), pound> {};
+struct grain : named_scaled_unit<grain, "gr", ratio(1, 7000), pound> {};
 
-struct dram : named_scaled_unit<dram, "dr", no_prefix, ratio(1, 256), pound> {};
+struct dram : named_scaled_unit<dram, "dr", ratio(1, 256), pound> {};
 
-struct ounce : named_scaled_unit<ounce, "oz", no_prefix, ratio(1, 16), pound> {};
+struct ounce : named_scaled_unit<ounce, "oz", ratio(1, 16), pound> {};
 
-struct stone : named_scaled_unit<stone, "st", no_prefix, ratio(14, 1), pound> {};
+struct stone : named_scaled_unit<stone, "st", ratio(14, 1), pound> {};
 
-struct quarter : named_scaled_unit<quarter, "qr", no_prefix, ratio(28, 1), pound> {};
+struct quarter : named_scaled_unit<quarter, "qr", ratio(28, 1), pound> {};
 
-struct hundredweight : named_scaled_unit<hundredweight, "cwt", no_prefix, ratio(112, 1), pound> {};
+struct hundredweight : named_scaled_unit<hundredweight, "cwt", ratio(112, 1), pound> {};
 
-struct short_ton : named_scaled_unit<short_ton, "ton (short)", no_prefix, ratio(2'000, 1), pound> {};
+struct short_ton : named_scaled_unit<short_ton, "ton (short)", ratio(2'000, 1), pound> {};
 
-struct long_ton : named_scaled_unit<long_ton, "ton (long)", no_prefix, ratio(2'240, 1), pound> {};
+struct long_ton : named_scaled_unit<long_ton, "ton (long)", ratio(2'240, 1), pound> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/power.h b/src/systems/si-fps/include/units/isq/si/fps/power.h
index d168ac6d..89b9243f 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/power.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/power.h
@@ -42,7 +42,7 @@ struct dim_power : isq::dim_power<dim_power, foot_poundal_per_second, dim_length
 struct foot_pound_force_per_second :
     derived_deduced_unit<foot_pound_force_per_second, dim_power, foot, pound_force, second> {};
 
-struct horse_power : named_scaled_unit<horse_power, "hp", no_prefix, ratio(550), foot_pound_force_per_second> {};
+struct horse_power : named_scaled_unit<horse_power, "hp", ratio(550), foot_pound_force_per_second> {};
 
 template<UnitOf<dim_power> U, Representation Rep = double>
 using power = quantity<dim_power, U, Rep>;
diff --git a/src/systems/si-fps/include/units/isq/si/fps/pressure.h b/src/systems/si-fps/include/units/isq/si/fps/pressure.h
index 84658252..31128c33 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/pressure.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/pressure.h
@@ -44,11 +44,10 @@ template<UnitOf<dim_pressure> U, Representation Rep = double>
 using pressure = quantity<dim_pressure, U, Rep>;
 
 struct pound_force_per_foot_sq :
-    named_scaled_unit<pound_force_per_foot_sq, "lbf ft2", si::prefix, ratio(32'174'049, 1'000'000),
-                      poundal_per_foot_sq> {};
+    named_scaled_unit<pound_force_per_foot_sq, "lbf ft2", ratio(32'174'049, 1'000'000), poundal_per_foot_sq> {};
 
 struct pound_force_per_inch_sq :
-    named_scaled_unit<pound_force_per_inch_sq, "psi", si::prefix, ratio(1, 144), pound_force_per_foot_sq> {};
+    named_scaled_unit<pound_force_per_inch_sq, "psi", ratio(1, 144), pound_force_per_foot_sq> {};
 
 struct kilopound_force_per_inch_sq : prefixed_unit<kilopound_force_per_inch_sq, si::kilo, pound_force_per_inch_sq> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/speed.h b/src/systems/si-fps/include/units/isq/si/fps/speed.h
index 0fb4fbb4..1f4916fd 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/speed.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/speed.h
@@ -43,7 +43,7 @@ using speed = quantity<dim_speed, U, Rep>;
 
 struct mile_per_hour : derived_deduced_unit<mile_per_hour, dim_speed, mile, hour> {};
 struct nautical_mile_per_hour : derived_deduced_unit<nautical_mile_per_hour, dim_speed, nautical_mile, hour> {};
-struct knot : alias_unit<nautical_mile_per_hour, "kn", no_prefix> {};
+struct knot : alias_unit<nautical_mile_per_hour, "kn"> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si-hep/include/units/isq/si/hep/area.h b/src/systems/si-hep/include/units/isq/si/hep/area.h
index da988438..dc8e5895 100644
--- a/src/systems/si-hep/include/units/isq/si/hep/area.h
+++ b/src/systems/si-hep/include/units/isq/si/hep/area.h
@@ -37,7 +37,7 @@ namespace units::isq::si::hep {
 // effective cross-sectional area according to EU council directive 80/181/EEC
 // https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:01980L0181-20090527#page=10
 // https://www.fedlex.admin.ch/eli/cc/1994/3109_3109_3109/de
-struct barn : named_scaled_unit<barn, "b", prefix, ratio(1, 1, -28), square_metre> {};
+struct barn : named_scaled_unit<barn, "b", ratio(1, 1, -28), square_metre> {};
 struct yocto_barn : prefixed_unit<yocto_barn, yocto, barn> {};
 struct zepto_barn : prefixed_unit<zepto_barn, zepto, barn> {};
 struct atto_barn : prefixed_unit<atto_barn, atto, barn> {};
diff --git a/src/systems/si-hep/include/units/isq/si/hep/mass.h b/src/systems/si-hep/include/units/isq/si/hep/mass.h
index 2f617544..10de3a3f 100644
--- a/src/systems/si-hep/include/units/isq/si/hep/mass.h
+++ b/src/systems/si-hep/include/units/isq/si/hep/mass.h
@@ -35,7 +35,7 @@
 namespace units::isq::si::hep {
 
 struct eV_per_c2 :
-    named_scaled_unit<eV_per_c2, basic_symbol_text{"eV/c²", "eV/c^2"}, prefix,
+    named_scaled_unit<eV_per_c2, basic_symbol_text{"eV/c²", "eV/c^2"},
                       ratio(1'7826'619'216'279, 1'000'000'000'000, -35), kilogram> {};
 struct feV_per_c2 : prefixed_unit<feV_per_c2, femto, eV_per_c2> {};
 struct peV_per_c2 : prefixed_unit<peV_per_c2, pico, eV_per_c2> {};
@@ -52,11 +52,10 @@ struct PeV_per_c2 : prefixed_unit<PeV_per_c2, peta, eV_per_c2> {};
 struct EeV_per_c2 : prefixed_unit<EeV_per_c2, exa, eV_per_c2> {};
 struct YeV_per_c2 : prefixed_unit<YeV_per_c2, yotta, eV_per_c2> {};
 struct electron_mass :
-    named_scaled_unit<eV_per_c2, "m_e", prefix, ratio(9'109'383'701'528, 1'000'000'000'000, -31), kilogram> {};
-struct proton_mass :
-    named_scaled_unit<eV_per_c2, "m_p", prefix, ratio(1'672'621'923'695, 1'000'000'000'000, -27), kilogram> {};
+    named_scaled_unit<eV_per_c2, "m_e", ratio(9'109'383'701'528, 1'000'000'000'000, -31), kilogram> {};
+struct proton_mass : named_scaled_unit<eV_per_c2, "m_p", ratio(1'672'621'923'695, 1'000'000'000'000, -27), kilogram> {};
 struct neutron_mass :
-    named_scaled_unit<eV_per_c2, "m_n", prefix, ratio(1'674'927'498'049, 1'000'000'000'000, -27), kilogram> {};
+    named_scaled_unit<eV_per_c2, "m_n", ratio(1'674'927'498'049, 1'000'000'000'000, -27), kilogram> {};
 
 struct dim_mass : isq::dim_mass<eV_per_c2> {};
 
diff --git a/src/systems/si-hep/include/units/isq/si/hep/momentum.h b/src/systems/si-hep/include/units/isq/si/hep/momentum.h
index 26417868..83557347 100644
--- a/src/systems/si-hep/include/units/isq/si/hep/momentum.h
+++ b/src/systems/si-hep/include/units/isq/si/hep/momentum.h
@@ -37,8 +37,7 @@ namespace units::isq::si::hep {
 struct kilogram_metre_per_second : derived_unit<kilogram_metre_per_second> {};
 
 struct eV_per_c :
-    named_scaled_unit<eV_per_c, "eV/c", prefix, ratio(5'344'285'992'678, 1'000'000'000'000, -35),
-                      kilogram_metre_per_second> {};
+    named_scaled_unit<eV_per_c, "eV/c", ratio(5'344'285'992'678, 1'000'000'000'000, -35), kilogram_metre_per_second> {};
 struct feV_per_c : prefixed_unit<feV_per_c, femto, eV_per_c> {};
 struct peV_per_c : prefixed_unit<peV_per_c, pico, eV_per_c> {};
 struct neV_per_c : prefixed_unit<neV_per_c, nano, eV_per_c> {};
diff --git a/src/systems/si-iau/include/units/isq/si/iau/length.h b/src/systems/si-iau/include/units/isq/si/iau/length.h
index ce0d1059..1c50ccc1 100644
--- a/src/systems/si-iau/include/units/isq/si/iau/length.h
+++ b/src/systems/si-iau/include/units/isq/si/iau/length.h
@@ -36,13 +36,13 @@
 namespace units::isq::si::iau {
 
 // https://en.wikipedia.org/wiki/Light-year
-struct light_year : named_scaled_unit<light_year, "ly", no_prefix, ratio(9460730472580800), si::metre> {};
+struct light_year : named_scaled_unit<light_year, "ly", ratio(9460730472580800), si::metre> {};
 
 // https://en.wikipedia.org/wiki/Parsec
-struct parsec : named_scaled_unit<parsec, "pc", si::prefix, ratio(30'856'775'814'913'673), si::metre> {};
+struct parsec : named_scaled_unit<parsec, "pc", ratio(30'856'775'814'913'673), si::metre> {};
 
 // https://en.wikipedia.org/wiki/Angstrom
-struct angstrom : named_scaled_unit<angstrom, "angstrom", no_prefix, ratio(1, 1, -10), si::metre> {};
+struct angstrom : named_scaled_unit<angstrom, "angstrom", ratio(1, 1, -10), si::metre> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si-imperial/include/units/isq/si/imperial/length.h b/src/systems/si-imperial/include/units/isq/si/imperial/length.h
index eb5978c3..8721ae4d 100644
--- a/src/systems/si-imperial/include/units/isq/si/imperial/length.h
+++ b/src/systems/si-imperial/include/units/isq/si/imperial/length.h
@@ -35,10 +35,10 @@
 namespace units::isq::si::imperial {
 
 // https://en.wikipedia.org/wiki/Chain_(unit)
-struct chain : named_scaled_unit<chain, "ch", no_prefix, ratio(22, 1), si::international::yard> {};
+struct chain : named_scaled_unit<chain, "ch", ratio(22, 1), si::international::yard> {};
 
 // https://en.wikipedia.org/wiki/Rod_(unit)
-struct rod : named_scaled_unit<rod, "rd", no_prefix, ratio(1, 4), chain> {};
+struct rod : named_scaled_unit<rod, "rd", ratio(1, 4), chain> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si-international/include/units/isq/si/international/length.h b/src/systems/si-international/include/units/isq/si/international/length.h
index ead14a46..4f93feae 100644
--- a/src/systems/si-international/include/units/isq/si/international/length.h
+++ b/src/systems/si-international/include/units/isq/si/international/length.h
@@ -37,30 +37,30 @@ namespace units::isq::si::international {
 
 // si::international yard
 // https://en.wikipedia.org/wiki/International_yard_and_pound
-struct yard : named_scaled_unit<yard, "yd", si::prefix, ratio(9'144, 1'000, -1), si::metre> {};
+struct yard : named_scaled_unit<yard, "yd", ratio(9'144, 1'000, -1), si::metre> {};
 
 // si::international foot
 // https://en.wikipedia.org/wiki/Foot_(unit)#International_foot
-struct foot : named_scaled_unit<foot, "ft", no_prefix, ratio(1, 3), yard> {};
+struct foot : named_scaled_unit<foot, "ft", ratio(1, 3), yard> {};
 
 // https://en.wikipedia.org/wiki/Fathom#International_fathom
-struct fathom : named_scaled_unit<fathom, "fathom", no_prefix, ratio(2), yard> {};
+struct fathom : named_scaled_unit<fathom, "fathom", ratio(2), yard> {};
 
 // si::international inch
 // https://en.wikipedia.org/wiki/Inch#Equivalences
-struct inch : named_scaled_unit<inch, "in", no_prefix, ratio(1, 36), yard> {};
+struct inch : named_scaled_unit<inch, "in", ratio(1, 36), yard> {};
 
 // intrnational mile
 // https://en.wikipedia.org/wiki/Mile#International_mile
-struct mile : named_scaled_unit<mile, "mi", no_prefix, ratio(25'146, 15'625), si::kilometre> {};
+struct mile : named_scaled_unit<mile, "mi", ratio(25'146, 15'625), si::kilometre> {};
 
 // si::international nautical mile
 // https://en.wikipedia.org/wiki/Nautical_mile
-struct nautical_mile : named_scaled_unit<nautical_mile, "nmi", no_prefix, ratio(1852), si::metre> {};
+struct nautical_mile : named_scaled_unit<nautical_mile, "nmi", ratio(1852), si::metre> {};
 
 // thou
 // https://en.wikipedia.org/wiki/Thousandth_of_an_inch
-struct thou : named_scaled_unit<thou, "thou", no_prefix, ratio(1, 1000), inch> {};
+struct thou : named_scaled_unit<thou, "thou", ratio(1, 1000), inch> {};
 
 // mil - different name for thou
 // https://en.wikipedia.org/wiki/Thousandth_of_an_inch
diff --git a/src/systems/si-international/include/units/isq/si/international/speed.h b/src/systems/si-international/include/units/isq/si/international/speed.h
index 16ef5a66..3081dd91 100644
--- a/src/systems/si-international/include/units/isq/si/international/speed.h
+++ b/src/systems/si-international/include/units/isq/si/international/speed.h
@@ -37,7 +37,7 @@ namespace units::isq::si::international {
 struct mile_per_hour : derived_deduced_unit<mile_per_hour, si::dim_speed, si::international::mile, si::hour> {};
 struct nautical_mile_per_hour :
     derived_deduced_unit<nautical_mile_per_hour, si::dim_speed, si::international::nautical_mile, si::hour> {};
-struct knot : alias_unit<nautical_mile_per_hour, "kn", no_prefix> {};
+struct knot : alias_unit<nautical_mile_per_hour, "kn"> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si-typographic/include/units/isq/si/typographic/length.h b/src/systems/si-typographic/include/units/isq/si/typographic/length.h
index cb3c691e..5e88390d 100644
--- a/src/systems/si-typographic/include/units/isq/si/typographic/length.h
+++ b/src/systems/si-typographic/include/units/isq/si/typographic/length.h
@@ -37,10 +37,10 @@ namespace units::isq::si::typographic {
 
 // TODO Conflicts with (https://en.wikipedia.org/wiki/Pica_(typography)), verify correctness of below conversion factors
 // and provide hyperlinks to definitions
-struct pica_comp : named_scaled_unit<pica_comp, "pica(comp)", no_prefix, ratio(4233333, 1000000, -3), si::metre> {};
-struct pica_prn : named_scaled_unit<pica_prn, "pica(prn)", no_prefix, ratio(2108759, 500000, -3), si::metre> {};
-struct point_comp : named_scaled_unit<point_comp, "point(comp)", no_prefix, ratio(1763889, 500000, -4), si::metre> {};
-struct point_prn : named_scaled_unit<point_prn, "point(prn)", no_prefix, ratio(1757299, 500000, -4), si::metre> {};
+struct pica_comp : named_scaled_unit<pica_comp, "pica(comp)", ratio(4233333, 1000000, -3), si::metre> {};
+struct pica_prn : named_scaled_unit<pica_prn, "pica(prn)", ratio(2108759, 500000, -3), si::metre> {};
+struct point_comp : named_scaled_unit<point_comp, "point(comp)", ratio(1763889, 500000, -4), si::metre> {};
+struct point_prn : named_scaled_unit<point_prn, "point(prn)", ratio(1757299, 500000, -4), si::metre> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si-uscs/include/units/isq/si/uscs/length.h b/src/systems/si-uscs/include/units/isq/si/uscs/length.h
index b1c06b5f..8c09a57d 100644
--- a/src/systems/si-uscs/include/units/isq/si/uscs/length.h
+++ b/src/systems/si-uscs/include/units/isq/si/uscs/length.h
@@ -36,14 +36,14 @@ namespace units::isq::si::uscs {
 
 // https://en.wikipedia.org/wiki/Foot_(unit)#US_survey_foot
 // https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors#B6
-struct foot : named_scaled_unit<foot, "ft(us)", no_prefix, ratio(1'200, 3'937), si::metre> {};
+struct foot : named_scaled_unit<foot, "ft(us)", ratio(1'200, 3'937), si::metre> {};
 
 // https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors#B6
-struct fathom : named_scaled_unit<fathom, "fathom(us)", no_prefix, ratio(6), foot> {};
+struct fathom : named_scaled_unit<fathom, "fathom(us)", ratio(6), foot> {};
 
 // https://en.wikipedia.org/wiki/Mile#U.S._survey_mile
 // https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors#B6
-struct mile : named_scaled_unit<mile, "mi(us)", no_prefix, ratio(5280), foot> {};
+struct mile : named_scaled_unit<mile, "mi(us)", ratio(5280), foot> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si/include/units/isq/si/absorbed_dose.h b/src/systems/si/include/units/isq/si/absorbed_dose.h
index 965665e8..40159573 100644
--- a/src/systems/si/include/units/isq/si/absorbed_dose.h
+++ b/src/systems/si/include/units/isq/si/absorbed_dose.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct gray : named_unit<gray, "Gy", prefix> {};
+struct gray : named_unit<gray, "Gy"> {};
 struct yoctogray : prefixed_unit<yoctogray, yocto, gray> {};
 struct zeptogray : prefixed_unit<zeptogray, zepto, gray> {};
 struct attogray : prefixed_unit<attogray, atto, gray> {};
diff --git a/src/systems/si/include/units/isq/si/amount_of_substance.h b/src/systems/si/include/units/isq/si/amount_of_substance.h
index e5d40c80..ba7578d8 100644
--- a/src/systems/si/include/units/isq/si/amount_of_substance.h
+++ b/src/systems/si/include/units/isq/si/amount_of_substance.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct mole : named_unit<mole, "mol", prefix> {};
+struct mole : named_unit<mole, "mol"> {};
 
 struct dim_amount_of_substance : isq::dim_amount_of_substance<mole> {};
 
diff --git a/src/systems/si/include/units/isq/si/angular_velocity.h b/src/systems/si/include/units/isq/si/angular_velocity.h
index 0cbcf686..4c606798 100644
--- a/src/systems/si/include/units/isq/si/angular_velocity.h
+++ b/src/systems/si/include/units/isq/si/angular_velocity.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct radian_per_second : named_unit<radian_per_second, basic_symbol_text{"ω", "w"}, prefix> {};
+struct radian_per_second : named_unit<radian_per_second, basic_symbol_text{"ω", "w"}> {};
 
 struct dim_angular_velocity :
     isq::dim_angular_velocity<dim_angular_velocity, radian_per_second, dim_angle<>, dim_time> {};
diff --git a/src/systems/si/include/units/isq/si/area.h b/src/systems/si/include/units/isq/si/area.h
index a3818096..f95dfc08 100644
--- a/src/systems/si/include/units/isq/si/area.h
+++ b/src/systems/si/include/units/isq/si/area.h
@@ -58,7 +58,7 @@ struct square_exametre : derived_deduced_unit<square_exametre, dim_area, exametr
 struct square_zettametre : derived_deduced_unit<square_zettametre, dim_area, zettametre> {};
 struct square_yottametre : derived_deduced_unit<square_yottametre, dim_area, yottametre> {};
 
-struct are : alias_unit<square_decametre, "a", prefix> {};
+struct are : alias_unit<square_decametre, "a"> {};
 struct centiare : prefixed_alias_unit<square_metre, centi, are> {};
 struct deciare : prefixed_unit<deciare, deci, are> {};
 struct decare : prefixed_unit<decare, deca, are> {};
diff --git a/src/systems/si/include/units/isq/si/capacitance.h b/src/systems/si/include/units/isq/si/capacitance.h
index ddea6793..31a477f9 100644
--- a/src/systems/si/include/units/isq/si/capacitance.h
+++ b/src/systems/si/include/units/isq/si/capacitance.h
@@ -36,7 +36,7 @@
 
 namespace units::isq::si {
 
-struct farad : named_unit<farad, "F", prefix> {};
+struct farad : named_unit<farad, "F"> {};
 struct yoctofarad : prefixed_unit<yoctofarad, yocto, farad> {};
 struct zeptofarad : prefixed_unit<zeptofarad, zepto, farad> {};
 struct attofarad : prefixed_unit<attofarad, atto, farad> {};
diff --git a/src/systems/si/include/units/isq/si/catalytic_activity.h b/src/systems/si/include/units/isq/si/catalytic_activity.h
index 9c348d88..d52e81ac 100644
--- a/src/systems/si/include/units/isq/si/catalytic_activity.h
+++ b/src/systems/si/include/units/isq/si/catalytic_activity.h
@@ -36,7 +36,7 @@
 
 namespace units::isq::si {
 
-struct katal : named_unit<katal, "kat", prefix> {};
+struct katal : named_unit<katal, "kat"> {};
 struct yoctokatal : prefixed_unit<yoctokatal, yocto, katal> {};
 struct zeptokatal : prefixed_unit<zeptokatal, zepto, katal> {};
 struct attokatal : prefixed_unit<attokatal, atto, katal> {};
@@ -58,7 +58,7 @@ struct exakatal : prefixed_unit<exakatal, exa, katal> {};
 struct zettakatal : prefixed_unit<zettakatal, zetta, katal> {};
 struct yottakatal : prefixed_unit<yottakatal, yotta, katal> {};
 
-struct enzyme_unit : named_scaled_unit<enzyme_unit, "U", prefix, ratio(1, 60, -6), katal> {};
+struct enzyme_unit : named_scaled_unit<enzyme_unit, "U", ratio(1, 60, -6), katal> {};
 
 struct dim_catalytic_activity :
     isq::dim_catalytic_activity<dim_catalytic_activity, katal, dim_time, dim_amount_of_substance> {};
diff --git a/src/systems/si/include/units/isq/si/conductance.h b/src/systems/si/include/units/isq/si/conductance.h
index 36b8cc13..5442201f 100644
--- a/src/systems/si/include/units/isq/si/conductance.h
+++ b/src/systems/si/include/units/isq/si/conductance.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct siemens : named_unit<siemens, "S", prefix> {};
+struct siemens : named_unit<siemens, "S"> {};
 struct yoctosiemens : prefixed_unit<yoctosiemens, yocto, siemens> {};
 struct zeptosiemens : prefixed_unit<zeptosiemens, zepto, siemens> {};
 struct attosiemens : prefixed_unit<attosiemens, atto, siemens> {};
diff --git a/src/systems/si/include/units/isq/si/electric_charge.h b/src/systems/si/include/units/isq/si/electric_charge.h
index cb79b848..ca431827 100644
--- a/src/systems/si/include/units/isq/si/electric_charge.h
+++ b/src/systems/si/include/units/isq/si/electric_charge.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct coulomb : named_unit<coulomb, "C", prefix> {};
+struct coulomb : named_unit<coulomb, "C"> {};
 
 struct dim_electric_charge : isq::dim_electric_charge<dim_electric_charge, coulomb, dim_time, dim_electric_current> {};
 
diff --git a/src/systems/si/include/units/isq/si/electric_current.h b/src/systems/si/include/units/isq/si/electric_current.h
index 23c12021..740eb113 100644
--- a/src/systems/si/include/units/isq/si/electric_current.h
+++ b/src/systems/si/include/units/isq/si/electric_current.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct ampere : named_unit<ampere, "A", prefix> {};
+struct ampere : named_unit<ampere, "A"> {};
 struct yoctoampere : prefixed_unit<yoctoampere, yocto, ampere> {};
 struct zeptoampere : prefixed_unit<zeptoampere, zepto, ampere> {};
 struct attoampere : prefixed_unit<attoampere, atto, ampere> {};
diff --git a/src/systems/si/include/units/isq/si/energy.h b/src/systems/si/include/units/isq/si/energy.h
index 2ca2fc9b..cb841b4b 100644
--- a/src/systems/si/include/units/isq/si/energy.h
+++ b/src/systems/si/include/units/isq/si/energy.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct joule : named_unit<joule, "J", prefix> {};
+struct joule : named_unit<joule, "J"> {};
 struct yoctojoule : prefixed_unit<yoctojoule, yocto, joule> {};
 struct zeptojoule : prefixed_unit<zeptojoule, zepto, joule> {};
 struct attojoule : prefixed_unit<attojoule, atto, joule> {};
@@ -55,7 +55,7 @@ struct yottajoule : prefixed_unit<yottajoule, yotta, joule> {};
 
 // N.B. electron charge (and eV) is an exact constant:
 // https://www.bipm.org/documents/20126/41483022/SI-Brochure-9.pdf#page=147
-struct electronvolt : named_scaled_unit<electronvolt, "eV", prefix, ratio(1'602'176'634, 1'000'000'000, -19), joule> {};
+struct electronvolt : named_scaled_unit<electronvolt, "eV", ratio(1'602'176'634, 1'000'000'000, -19), joule> {};
 struct gigaelectronvolt : prefixed_unit<gigaelectronvolt, giga, electronvolt> {};
 
 struct dim_energy : isq::dim_energy<dim_energy, joule, dim_force, dim_length> {};
diff --git a/src/systems/si/include/units/isq/si/force.h b/src/systems/si/include/units/isq/si/force.h
index c0977aaf..fa2c1880 100644
--- a/src/systems/si/include/units/isq/si/force.h
+++ b/src/systems/si/include/units/isq/si/force.h
@@ -36,7 +36,7 @@
 
 namespace units::isq::si {
 
-struct newton : named_unit<newton, "N", prefix> {};
+struct newton : named_unit<newton, "N"> {};
 struct yoctonewton : prefixed_unit<yoctonewton, yocto, newton> {};
 struct zeptonewton : prefixed_unit<zeptonewton, zepto, newton> {};
 struct attonewton : prefixed_unit<attonewton, atto, newton> {};
diff --git a/src/systems/si/include/units/isq/si/frequency.h b/src/systems/si/include/units/isq/si/frequency.h
index 0a9bd90a..39fa13ee 100644
--- a/src/systems/si/include/units/isq/si/frequency.h
+++ b/src/systems/si/include/units/isq/si/frequency.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct hertz : named_unit<hertz, "Hz", prefix> {};
+struct hertz : named_unit<hertz, "Hz"> {};
 struct yoctohertz : prefixed_unit<yoctohertz, yocto, hertz> {};
 struct zeptohertz : prefixed_unit<zeptohertz, zepto, hertz> {};
 struct attohertz : prefixed_unit<attohertz, atto, hertz> {};
diff --git a/src/systems/si/include/units/isq/si/inductance.h b/src/systems/si/include/units/isq/si/inductance.h
index e3eb6ee7..c6a14a98 100644
--- a/src/systems/si/include/units/isq/si/inductance.h
+++ b/src/systems/si/include/units/isq/si/inductance.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct henry : named_unit<henry, "H", prefix> {};
+struct henry : named_unit<henry, "H"> {};
 
 struct yoctohenry : prefixed_unit<yoctohenry, yocto, henry> {};
 struct zeptohenry : prefixed_unit<zeptohenry, zepto, henry> {};
diff --git a/src/systems/si/include/units/isq/si/length.h b/src/systems/si/include/units/isq/si/length.h
index 36022dbd..0e7f28fd 100644
--- a/src/systems/si/include/units/isq/si/length.h
+++ b/src/systems/si/include/units/isq/si/length.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct metre : named_unit<metre, "m", prefix> {};
+struct metre : named_unit<metre, "m"> {};
 struct yoctometre : prefixed_unit<yoctometre, yocto, metre> {};
 struct zeptometre : prefixed_unit<zeptometre, zepto, metre> {};
 struct attometre : prefixed_unit<attometre, atto, metre> {};
@@ -56,7 +56,7 @@ struct exametre : prefixed_unit<exametre, exa, metre> {};
 struct zettametre : prefixed_unit<zettametre, zetta, metre> {};
 struct yottametre : prefixed_unit<yottametre, yotta, metre> {};
 
-struct astronomical_unit : named_scaled_unit<astronomical_unit, "au", prefix, ratio(149'597'870'700), metre> {};
+struct astronomical_unit : named_scaled_unit<astronomical_unit, "au", ratio(149'597'870'700), metre> {};
 
 struct dim_length : isq::dim_length<metre> {};
 
diff --git a/src/systems/si/include/units/isq/si/luminous_intensity.h b/src/systems/si/include/units/isq/si/luminous_intensity.h
index e4eff3c5..38e658f0 100644
--- a/src/systems/si/include/units/isq/si/luminous_intensity.h
+++ b/src/systems/si/include/units/isq/si/luminous_intensity.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct candela : named_unit<candela, "cd", prefix> {};
+struct candela : named_unit<candela, "cd"> {};
 struct yoctocandela : prefixed_unit<yoctocandela, yocto, candela> {};
 struct zeptocandela : prefixed_unit<zeptocandela, zepto, candela> {};
 struct attocandela : prefixed_unit<attocandela, atto, candela> {};
diff --git a/src/systems/si/include/units/isq/si/magnetic_flux.h b/src/systems/si/include/units/isq/si/magnetic_flux.h
index 57c1317d..77b1410c 100644
--- a/src/systems/si/include/units/isq/si/magnetic_flux.h
+++ b/src/systems/si/include/units/isq/si/magnetic_flux.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct weber : named_unit<weber, "Wb", prefix> {};
+struct weber : named_unit<weber, "Wb"> {};
 
 struct yoctoweber : prefixed_unit<yoctoweber, yocto, weber> {};
 struct zeptoweber : prefixed_unit<zeptoweber, zepto, weber> {};
diff --git a/src/systems/si/include/units/isq/si/magnetic_induction.h b/src/systems/si/include/units/isq/si/magnetic_induction.h
index 353a3af0..a1a7f507 100644
--- a/src/systems/si/include/units/isq/si/magnetic_induction.h
+++ b/src/systems/si/include/units/isq/si/magnetic_induction.h
@@ -37,7 +37,7 @@
 
 namespace units::isq::si {
 
-struct tesla : named_unit<tesla, "T", prefix> {};
+struct tesla : named_unit<tesla, "T"> {};
 
 struct yoctotesla : prefixed_unit<yoctotesla, yocto, tesla> {};
 struct zeptotesla : prefixed_unit<zeptotesla, zepto, tesla> {};
@@ -56,7 +56,7 @@ struct exatesla : prefixed_unit<exatesla, exa, tesla> {};
 struct zettatesla : prefixed_unit<zettatesla, zetta, tesla> {};
 struct yottatesla : prefixed_unit<yottatesla, yotta, tesla> {};
 
-struct gauss : named_scaled_unit<gauss, "G", prefix, ratio(1, 10'000), tesla> {};
+struct gauss : named_scaled_unit<gauss, "G", ratio(1, 10'000), tesla> {};
 
 struct dim_magnetic_induction :
     isq::dim_magnetic_induction<dim_magnetic_induction, tesla, dim_voltage, dim_time, dim_length> {};
diff --git a/src/systems/si/include/units/isq/si/mass.h b/src/systems/si/include/units/isq/si/mass.h
index 89776694..dd877f26 100644
--- a/src/systems/si/include/units/isq/si/mass.h
+++ b/src/systems/si/include/units/isq/si/mass.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct gram : named_unit<gram, "g", prefix> {};
+struct gram : named_unit<gram, "g"> {};
 struct yoctogram : prefixed_unit<yoctogram, yocto, gram> {};
 struct zeptogram : prefixed_unit<zeptogram, zepto, gram> {};
 struct attogram : prefixed_unit<attogram, atto, gram> {};
@@ -56,7 +56,7 @@ struct exagram : prefixed_unit<exagram, exa, gram> {};
 struct zettagram : prefixed_unit<zettagram, zetta, gram> {};
 struct yottagram : prefixed_unit<yottagram, yotta, gram> {};
 
-struct tonne : alias_unit<megagram, "t", prefix> {};
+struct tonne : alias_unit<megagram, "t"> {};
 struct yoctotonne : prefixed_alias_unit<attogram, yocto, tonne> {};
 struct zeptotonne : prefixed_alias_unit<femtogram, zepto, tonne> {};
 struct attotonne : prefixed_alias_unit<picogram, atto, tonne> {};
@@ -78,8 +78,7 @@ struct exatonne : prefixed_alias_unit<yottagram, exa, tonne> {};
 struct zettatonne : prefixed_unit<zettatonne, zetta, tonne> {};
 struct yottatonne : prefixed_unit<yottatonne, yotta, tonne> {};
 
-struct dalton :
-    named_scaled_unit<dalton, "Da", prefix, ratio(16'605'390'666'050, 10'000'000'000'000, -27), kilogram> {};
+struct dalton : named_scaled_unit<dalton, "Da", ratio(16'605'390'666'050, 10'000'000'000'000, -27), kilogram> {};
 
 struct dim_mass : isq::dim_mass<kilogram> {};
 
diff --git a/src/systems/si/include/units/isq/si/power.h b/src/systems/si/include/units/isq/si/power.h
index 360e92e9..d95d5c30 100644
--- a/src/systems/si/include/units/isq/si/power.h
+++ b/src/systems/si/include/units/isq/si/power.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si {
 
-struct watt : named_unit<watt, "W", prefix> {};
+struct watt : named_unit<watt, "W"> {};
 struct yoctowatt : prefixed_unit<yoctowatt, yocto, watt> {};
 struct zeptowatt : prefixed_unit<zeptowatt, zepto, watt> {};
 struct attowatt : prefixed_unit<attowatt, atto, watt> {};
diff --git a/src/systems/si/include/units/isq/si/prefixes.h b/src/systems/si/include/units/isq/si/prefixes.h
index a6e9cd08..0efabcf3 100644
--- a/src/systems/si/include/units/isq/si/prefixes.h
+++ b/src/systems/si/include/units/isq/si/prefixes.h
@@ -26,29 +26,27 @@
 
 namespace units::isq::si {
 
-struct prefix : prefix_family {};
-
 // clang-format off
-struct yocto  : units::prefix<yocto,  prefix, "y",             ratio(1, 1, -24)> {};
-struct zepto  : units::prefix<zepto,  prefix, "z",             ratio(1, 1, -21)> {};
-struct atto   : units::prefix<atto,   prefix, "a",             ratio(1, 1, -18)> {};
-struct femto  : units::prefix<femto,  prefix, "f",             ratio(1, 1, -15)> {};
-struct pico   : units::prefix<pico,   prefix, "p",             ratio(1, 1, -12)> {};
-struct nano   : units::prefix<nano,   prefix, "n",             ratio(1, 1,  -9)> {};
-struct micro  : units::prefix<micro,  prefix, basic_symbol_text{"\u00b5", "u"}, ratio(1, 1,  -6)> {};
-struct milli  : units::prefix<milli,  prefix, "m",             ratio(1, 1,  -3)> {};
-struct centi  : units::prefix<centi,  prefix, "c",             ratio(1, 1,  -2)> {};
-struct deci   : units::prefix<deci,   prefix, "d",             ratio(1, 1,  -1)> {};
-struct deca   : units::prefix<deca,   prefix, "da",            ratio(1, 1,   1)> {};
-struct hecto  : units::prefix<hecto,  prefix, "h",             ratio(1, 1,   2)> {};
-struct kilo   : units::prefix<kilo,   prefix, "k",             ratio(1, 1,   3)> {};
-struct mega   : units::prefix<mega,   prefix, "M",             ratio(1, 1,   6)> {};
-struct giga   : units::prefix<giga,   prefix, "G",             ratio(1, 1,   9)> {};
-struct tera   : units::prefix<tera,   prefix, "T",             ratio(1, 1,  12)> {};
-struct peta   : units::prefix<peta,   prefix, "P",             ratio(1, 1,  15)> {};
-struct exa    : units::prefix<exa,    prefix, "E",             ratio(1, 1,  18)> {};
-struct zetta  : units::prefix<zetta,  prefix, "Z",             ratio(1, 1,  21)> {};
-struct yotta  : units::prefix<yotta,  prefix, "Y",             ratio(1, 1,  24)> {};
+struct yocto  : units::prefix<yocto, "y",             ratio(1, 1, -24)> {};
+struct zepto  : units::prefix<zepto, "z",             ratio(1, 1, -21)> {};
+struct atto   : units::prefix<atto,  "a",             ratio(1, 1, -18)> {};
+struct femto  : units::prefix<femto, "f",             ratio(1, 1, -15)> {};
+struct pico   : units::prefix<pico,  "p",             ratio(1, 1, -12)> {};
+struct nano   : units::prefix<nano,  "n",             ratio(1, 1,  -9)> {};
+struct micro  : units::prefix<micro, basic_symbol_text{"\u00b5", "u"}, ratio(1, 1,  -6)> {};
+struct milli  : units::prefix<milli, "m",             ratio(1, 1,  -3)> {};
+struct centi  : units::prefix<centi, "c",             ratio(1, 1,  -2)> {};
+struct deci   : units::prefix<deci,  "d",             ratio(1, 1,  -1)> {};
+struct deca   : units::prefix<deca,  "da",            ratio(1, 1,   1)> {};
+struct hecto  : units::prefix<hecto, "h",             ratio(1, 1,   2)> {};
+struct kilo   : units::prefix<kilo,  "k",             ratio(1, 1,   3)> {};
+struct mega   : units::prefix<mega,  "M",             ratio(1, 1,   6)> {};
+struct giga   : units::prefix<giga,  "G",             ratio(1, 1,   9)> {};
+struct tera   : units::prefix<tera,  "T",             ratio(1, 1,  12)> {};
+struct peta   : units::prefix<peta,  "P",             ratio(1, 1,  15)> {};
+struct exa    : units::prefix<exa,   "E",             ratio(1, 1,  18)> {};
+struct zetta  : units::prefix<zetta, "Z",             ratio(1, 1,  21)> {};
+struct yotta  : units::prefix<yotta, "Y",             ratio(1, 1,  24)> {};
 // clang-format on
 
 }  // namespace units::isq::si
diff --git a/src/systems/si/include/units/isq/si/pressure.h b/src/systems/si/include/units/isq/si/pressure.h
index b3c94279..86bed5d2 100644
--- a/src/systems/si/include/units/isq/si/pressure.h
+++ b/src/systems/si/include/units/isq/si/pressure.h
@@ -36,7 +36,7 @@
 
 namespace units::isq::si {
 
-struct pascal : named_unit<pascal, "Pa", prefix> {};
+struct pascal : named_unit<pascal, "Pa"> {};
 struct yoctopascal : prefixed_unit<yoctopascal, yocto, pascal> {};
 struct zeptopascal : prefixed_unit<zeptopascal, zepto, pascal> {};
 struct attopascal : prefixed_unit<attopascal, atto, pascal> {};
diff --git a/src/systems/si/include/units/isq/si/radioactivity.h b/src/systems/si/include/units/isq/si/radioactivity.h
index 7db478d1..d46c81e4 100644
--- a/src/systems/si/include/units/isq/si/radioactivity.h
+++ b/src/systems/si/include/units/isq/si/radioactivity.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct becquerel : named_unit<becquerel, "Bq", prefix> {};
+struct becquerel : named_unit<becquerel, "Bq"> {};
 struct yoctobecquerel : prefixed_unit<yoctobecquerel, yocto, becquerel> {};
 struct zeptobecquerel : prefixed_unit<zeptobecquerel, zepto, becquerel> {};
 struct attobecquerel : prefixed_unit<attobecquerel, atto, becquerel> {};
diff --git a/src/systems/si/include/units/isq/si/resistance.h b/src/systems/si/include/units/isq/si/resistance.h
index 83d3fca0..ea57ed61 100644
--- a/src/systems/si/include/units/isq/si/resistance.h
+++ b/src/systems/si/include/units/isq/si/resistance.h
@@ -36,7 +36,7 @@
 
 namespace units::isq::si {
 
-struct ohm : named_unit<ohm, basic_symbol_text{"Ω", "ohm"}, prefix> {};
+struct ohm : named_unit<ohm, basic_symbol_text{"Ω", "ohm"}> {};
 struct yoctoohm : prefixed_unit<yoctoohm, yocto, ohm> {};
 struct zeptoohm : prefixed_unit<zeptoohm, zepto, ohm> {};
 struct attoohm : prefixed_unit<attoohm, atto, ohm> {};
diff --git a/src/systems/si/include/units/isq/si/thermodynamic_temperature.h b/src/systems/si/include/units/isq/si/thermodynamic_temperature.h
index 04e81c35..cc0e3206 100644
--- a/src/systems/si/include/units/isq/si/thermodynamic_temperature.h
+++ b/src/systems/si/include/units/isq/si/thermodynamic_temperature.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct kelvin : named_unit<kelvin, "K", prefix> {};
+struct kelvin : named_unit<kelvin, "K"> {};
 
 struct dim_thermodynamic_temperature : isq::dim_thermodynamic_temperature<kelvin> {};
 
diff --git a/src/systems/si/include/units/isq/si/time.h b/src/systems/si/include/units/isq/si/time.h
index 7c1d4d5c..7c855957 100644
--- a/src/systems/si/include/units/isq/si/time.h
+++ b/src/systems/si/include/units/isq/si/time.h
@@ -34,7 +34,7 @@
 
 namespace units::isq::si {
 
-struct second : named_unit<second, "s", prefix> {};
+struct second : named_unit<second, "s"> {};
 struct yoctosecond : prefixed_unit<yoctosecond, yocto, second> {};
 struct zeptosecond : prefixed_unit<zeptosecond, zepto, second> {};
 struct attosecond : prefixed_unit<attosecond, atto, second> {};
@@ -43,9 +43,9 @@ struct picosecond : prefixed_unit<picosecond, pico, second> {};
 struct nanosecond : prefixed_unit<nanosecond, nano, second> {};
 struct microsecond : prefixed_unit<microsecond, micro, second> {};
 struct millisecond : prefixed_unit<millisecond, milli, second> {};
-struct minute : named_scaled_unit<minute, "min", no_prefix, ratio(60), second> {};
-struct hour : named_scaled_unit<hour, "h", no_prefix, ratio(60), minute> {};
-struct day : named_scaled_unit<day, "d", no_prefix, ratio(24), hour> {};
+struct minute : named_scaled_unit<minute, "min", ratio(60), second> {};
+struct hour : named_scaled_unit<hour, "h", ratio(60), minute> {};
+struct day : named_scaled_unit<day, "d", ratio(24), hour> {};
 
 struct dim_time : isq::dim_time<second> {};
 
diff --git a/src/systems/si/include/units/isq/si/voltage.h b/src/systems/si/include/units/isq/si/voltage.h
index 31922688..e06cc1be 100644
--- a/src/systems/si/include/units/isq/si/voltage.h
+++ b/src/systems/si/include/units/isq/si/voltage.h
@@ -36,7 +36,7 @@
 
 namespace units::isq::si {
 
-struct volt : named_unit<volt, "V", prefix> {};
+struct volt : named_unit<volt, "V"> {};
 struct yoctovolt : prefixed_unit<yoctovolt, yocto, volt> {};
 struct zeptovolt : prefixed_unit<zeptovolt, zepto, volt> {};
 struct attovolt : prefixed_unit<attovolt, atto, volt> {};
diff --git a/src/systems/si/include/units/isq/si/volume.h b/src/systems/si/include/units/isq/si/volume.h
index a1f77b6e..d85c4f43 100644
--- a/src/systems/si/include/units/isq/si/volume.h
+++ b/src/systems/si/include/units/isq/si/volume.h
@@ -58,7 +58,7 @@ struct cubic_exametre : derived_deduced_unit<cubic_exametre, dim_volume, exametr
 struct cubic_zettametre : derived_deduced_unit<cubic_zettametre, dim_volume, zettametre> {};
 struct cubic_yottametre : derived_deduced_unit<cubic_yottametre, dim_volume, yottametre> {};
 
-struct litre : alias_unit<cubic_decimetre, "l", prefix> {};
+struct litre : alias_unit<cubic_decimetre, "l"> {};
 struct yoctolitre : prefixed_alias_unit<cubic_nanometre, yocto, litre> {};
 struct zeptolitre : prefixed_unit<zeptolitre, zepto, litre> {};
 struct attolitre : prefixed_unit<attolitre, atto, litre> {};
diff --git a/test/unit_test/static/concepts_test.cpp b/test/unit_test/static/concepts_test.cpp
index d1c1e2bf..b0e62788 100644
--- a/test/unit_test/static/concepts_test.cpp
+++ b/test/unit_test/static/concepts_test.cpp
@@ -42,15 +42,9 @@ namespace {
 using namespace units;
 using namespace units::isq;
 
-// Prefix family
-
-static_assert(PrefixFamily<si::prefix>);
-static_assert(!PrefixFamily<si::kilo>);
-
 // Prefix
 
 static_assert(Prefix<si::kilo>);
-static_assert(!Prefix<si::prefix>);
 static_assert(!Prefix<std::kilo>);
 
 // UnitRatio
@@ -92,6 +86,13 @@ static_assert(!Unit<si::dim_length>);
 static_assert(!Unit<int>);
 static_assert(!Unit<std::chrono::seconds>);
 
+// NamedUnit
+
+static_assert(NamedUnit<si::metre>);
+static_assert(NamedUnit<si::kilometre>);
+static_assert(NamedUnit<si::fps::mile>);
+static_assert(!NamedUnit<si::metre_per_second>);
+
 // UnitOf
 
 static_assert(UnitOf<si::metre, si::dim_length>);
diff --git a/test/unit_test/static/dimension_op_test.cpp b/test/unit_test/static/dimension_op_test.cpp
index 61de01f9..fe1561cb 100644
--- a/test/unit_test/static/dimension_op_test.cpp
+++ b/test/unit_test/static/dimension_op_test.cpp
@@ -30,13 +30,13 @@ using namespace units;
 
 namespace {
 
-struct u0 : named_unit<u0, "u0", no_prefix> {};
+struct u0 : named_unit<u0, "u0"> {};
 struct d0 : base_dimension<"d0", u0> {};
-struct u1 : named_unit<u1, "u1", no_prefix> {};
+struct u1 : named_unit<u1, "u1"> {};
 struct d1 : base_dimension<"d1", u1> {};
-struct u2 : named_unit<u2, "u2", no_prefix> {};
+struct u2 : named_unit<u2, "u2"> {};
 struct d2 : base_dimension<"d2", u2> {};
-struct u3 : named_unit<u3, "u3", no_prefix> {};
+struct u3 : named_unit<u3, "u3"> {};
 struct d3 : base_dimension<"d3", u3> {};
 
 // exponent_invert
diff --git a/test/unit_test/static/type_list_test.cpp b/test/unit_test/static/type_list_test.cpp
index 186e0ba0..81f39586 100644
--- a/test/unit_test/static/type_list_test.cpp
+++ b/test/unit_test/static/type_list_test.cpp
@@ -94,9 +94,9 @@ static_assert(
   is_same_v<type_list_split_half<type_list<int, long, double, float>>::second_list, type_list<double, float>>);
 
 // type_list_merge_sorted
-struct u0 : named_unit<u0, "u0", no_prefix> {};
+struct u0 : named_unit<u0, "u0"> {};
 struct d0 : base_dimension<"d0", u0> {};
-struct u1 : named_unit<u1, "u1", no_prefix> {};
+struct u1 : named_unit<u1, "u1"> {};
 struct d1 : base_dimension<"d1", u1> {};
 
 static_assert(
diff --git a/test/unit_test/static/unit_test.cpp b/test/unit_test/static/unit_test.cpp
index ddd97b88..6a22b013 100644
--- a/test/unit_test/static/unit_test.cpp
+++ b/test/unit_test/static/unit_test.cpp
@@ -33,22 +33,22 @@ namespace {
 using namespace units;
 using namespace units::isq;
 
-struct metre : named_unit<metre, "m", si::prefix> {};
+struct metre : named_unit<metre, "m"> {};
 struct centimetre : prefixed_unit<centimetre, si::centi, metre> {};
 struct kilometre : prefixed_unit<kilometre, si::kilo, metre> {};
-struct yard : named_scaled_unit<yard, "yd", no_prefix, ratio(9'144, 1, -4), metre> {};
-struct foot : named_scaled_unit<foot, "ft", no_prefix, ratio(1, 3), yard> {};
+struct yard : named_scaled_unit<yard, "yd", ratio(9'144, 1, -4), metre> {};
+struct foot : named_scaled_unit<foot, "ft", ratio(1, 3), yard> {};
 struct dim_length : base_dimension<"length", metre> {};
 
-struct second : named_unit<second, "s", si::prefix> {};
-struct hour : named_scaled_unit<hour, "h", no_prefix, ratio(36, 1, 2), second> {};
+struct second : named_unit<second, "s"> {};
+struct hour : named_scaled_unit<hour, "h", ratio(36, 1, 2), second> {};
 struct dim_time : base_dimension<"time", second> {};
 
-struct kelvin : named_unit<kelvin, "K", no_prefix> {};
+struct kelvin : named_unit<kelvin, "K"> {};
 
 #if !UNITS_COMP_MSVC
 static_assert([]<Prefix P>(P) {
-  return !requires { typename prefixed_unit<struct kilokelvin, P, kelvin>; };
+  return !requires { typename prefixed_unit<struct kilokilometre, P, kilometre>; };
 }(si::kilo{}));  // no prefix allowed
 #endif
 

From 5300caf17b08c1540a7d7ce7817aca164ef571b8 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 12:34:52 +0200
Subject: [PATCH 46/68] refactor: :boom: ! `derived_deduced_unit` renamed to
 `derived_scaled_unit`

Naming is hard ;-)
---
 ...d_deduced_unit.h => derived_scaled_unit.h} |  4 +-
 src/core/include/units/unit.h                 |  4 +-
 .../units/isq/iec80000/transfer_rate.h        | 16 ++++----
 .../si-fps/include/units/isq/si/fps/energy.h  |  2 +-
 .../si-fps/include/units/isq/si/fps/power.h   |  2 +-
 .../si-fps/include/units/isq/si/fps/speed.h   |  4 +-
 .../si-fps/include/units/isq/si/fps/volume.h  |  2 +-
 .../include/units/isq/si/international/area.h |  2 +-
 .../units/isq/si/international/speed.h        |  4 +-
 .../units/isq/si/international/volume.h       |  2 +-
 src/systems/si/include/units/isq/si/area.h    | 40 +++++++++----------
 src/systems/si/include/units/isq/si/speed.h   |  2 +-
 src/systems/si/include/units/isq/si/volume.h  | 40 +++++++++----------
 test/unit_test/runtime/fmt_test.cpp           |  2 +-
 test/unit_test/static/custom_unit_test.cpp    |  2 +-
 test/unit_test/static/unit_test.cpp           |  2 +-
 16 files changed, 65 insertions(+), 65 deletions(-)
 rename src/core/include/units/bits/{derived_deduced_unit.h => derived_scaled_unit.h} (97%)

diff --git a/src/core/include/units/bits/derived_deduced_unit.h b/src/core/include/units/bits/derived_scaled_unit.h
similarity index 97%
rename from src/core/include/units/bits/derived_deduced_unit.h
rename to src/core/include/units/bits/derived_scaled_unit.h
index 86f3f523..e94c7636 100644
--- a/src/core/include/units/bits/derived_deduced_unit.h
+++ b/src/core/include/units/bits/derived_scaled_unit.h
@@ -33,7 +33,7 @@ inline constexpr bool same_scaled_units = false;
 template<typename... Es, Unit... Us>
 inline constexpr bool same_scaled_units<exponent_list<Es...>, Us...> = (UnitOf<Us, typename Es::dimension> && ...);
 
-// derived_deduced_unit
+// derived_scaled_unit
 
 template<Exponent E>
 constexpr ratio inverse_if_negative(const ratio& r)
@@ -52,7 +52,7 @@ constexpr ratio derived_ratio(exponent_list<Es...>)
 }
 
 template<DerivedDimension D, Unit... Us>
-using derived_deduced_unit =
+using derived_scaled_unit =
   scaled_unit<derived_ratio<Us...>(typename D::recipe()), typename D::coherent_unit::reference>;
 
 }  // namespace units::detail
diff --git a/src/core/include/units/unit.h b/src/core/include/units/unit.h
index 386e360e..6e8ed3ca 100644
--- a/src/core/include/units/unit.h
+++ b/src/core/include/units/unit.h
@@ -26,7 +26,7 @@
 #include <units/bits/external/downcasting.h>
 
 // IWYU pragma: begin_exports
-#include <units/bits/derived_deduced_unit.h>
+#include <units/bits/derived_scaled_unit.h>
 #include <units/bits/external/fixed_string.h>
 #include <units/prefix.h>
 #include <units/ratio.h>
@@ -146,7 +146,7 @@ struct derived_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {};
  */
 template<typename Child, DerivedDimension Dim, NamedUnit U, NamedUnit... URest>
   requires detail::same_scaled_units<typename Dim::recipe, U, URest...>
-struct derived_deduced_unit : downcast_dispatch<Child, detail::derived_deduced_unit<Dim, U, URest...>> {
+struct derived_scaled_unit : downcast_dispatch<Child, detail::derived_scaled_unit<Dim, U, URest...>> {
   static constexpr auto symbol = detail::derived_symbol_text<Dim, U, URest...>();
 };
 
diff --git a/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h b/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h
index ce22f0f3..54a02d7e 100644
--- a/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h
+++ b/src/systems/isq-iec80000/include/units/isq/iec80000/transfer_rate.h
@@ -39,14 +39,14 @@ struct dim_transfer_rate :
     derived_dimension<dim_transfer_rate, byte_per_second, exponent<dim_storage_capacity, 1>,
                       exponent<si::dim_time, -1>> {};
 
-struct kilobyte_per_second : derived_deduced_unit<kilobyte_per_second, dim_transfer_rate, kilobyte, si::second> {};
-struct megabyte_per_second : derived_deduced_unit<megabyte_per_second, dim_transfer_rate, megabyte, si::second> {};
-struct gigabyte_per_second : derived_deduced_unit<gigabyte_per_second, dim_transfer_rate, gigabyte, si::second> {};
-struct terabyte_per_second : derived_deduced_unit<terabyte_per_second, dim_transfer_rate, terabyte, si::second> {};
-struct petabyte_per_second : derived_deduced_unit<petabyte_per_second, dim_transfer_rate, petabyte, si::second> {};
-struct exabyte_per_second : derived_deduced_unit<exabyte_per_second, dim_transfer_rate, exabyte, si::second> {};
-struct zettabyte_per_second : derived_deduced_unit<zettabyte_per_second, dim_transfer_rate, zettabyte, si::second> {};
-struct yottabyte_per_second : derived_deduced_unit<yottabyte_per_second, dim_transfer_rate, yottabyte, si::second> {};
+struct kilobyte_per_second : derived_scaled_unit<kilobyte_per_second, dim_transfer_rate, kilobyte, si::second> {};
+struct megabyte_per_second : derived_scaled_unit<megabyte_per_second, dim_transfer_rate, megabyte, si::second> {};
+struct gigabyte_per_second : derived_scaled_unit<gigabyte_per_second, dim_transfer_rate, gigabyte, si::second> {};
+struct terabyte_per_second : derived_scaled_unit<terabyte_per_second, dim_transfer_rate, terabyte, si::second> {};
+struct petabyte_per_second : derived_scaled_unit<petabyte_per_second, dim_transfer_rate, petabyte, si::second> {};
+struct exabyte_per_second : derived_scaled_unit<exabyte_per_second, dim_transfer_rate, exabyte, si::second> {};
+struct zettabyte_per_second : derived_scaled_unit<zettabyte_per_second, dim_transfer_rate, zettabyte, si::second> {};
+struct yottabyte_per_second : derived_scaled_unit<yottabyte_per_second, dim_transfer_rate, yottabyte, si::second> {};
 
 template<typename T>
 concept TransferRate = QuantityOf<T, dim_transfer_rate>;
diff --git a/src/systems/si-fps/include/units/isq/si/fps/energy.h b/src/systems/si-fps/include/units/isq/si/fps/energy.h
index 94bdac0d..593319a0 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/energy.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/energy.h
@@ -40,7 +40,7 @@ struct foot_poundal : derived_unit<foot_poundal> {};
 struct dim_energy : isq::dim_energy<dim_energy, foot_poundal, dim_length, dim_force> {};
 
 // https://en.wikipedia.org/wiki/Foot-pound_(energy)
-struct foot_pound_force : derived_deduced_unit<foot_pound_force, dim_energy, foot, pound_force> {};
+struct foot_pound_force : derived_scaled_unit<foot_pound_force, dim_energy, foot, pound_force> {};
 
 template<UnitOf<dim_energy> U, Representation Rep = double>
 using energy = quantity<dim_energy, U, Rep>;
diff --git a/src/systems/si-fps/include/units/isq/si/fps/power.h b/src/systems/si-fps/include/units/isq/si/fps/power.h
index 89b9243f..8126702f 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/power.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/power.h
@@ -40,7 +40,7 @@ struct foot_poundal_per_second : derived_unit<foot_poundal_per_second> {};
 struct dim_power : isq::dim_power<dim_power, foot_poundal_per_second, dim_length, dim_force, dim_time> {};
 
 struct foot_pound_force_per_second :
-    derived_deduced_unit<foot_pound_force_per_second, dim_power, foot, pound_force, second> {};
+    derived_scaled_unit<foot_pound_force_per_second, dim_power, foot, pound_force, second> {};
 
 struct horse_power : named_scaled_unit<horse_power, "hp", ratio(550), foot_pound_force_per_second> {};
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/speed.h b/src/systems/si-fps/include/units/isq/si/fps/speed.h
index 1f4916fd..6ec5944d 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/speed.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/speed.h
@@ -41,8 +41,8 @@ struct dim_speed : isq::dim_speed<dim_speed, foot_per_second, dim_length, dim_ti
 template<UnitOf<dim_speed> U, Representation Rep = double>
 using speed = quantity<dim_speed, U, Rep>;
 
-struct mile_per_hour : derived_deduced_unit<mile_per_hour, dim_speed, mile, hour> {};
-struct nautical_mile_per_hour : derived_deduced_unit<nautical_mile_per_hour, dim_speed, nautical_mile, hour> {};
+struct mile_per_hour : derived_scaled_unit<mile_per_hour, dim_speed, mile, hour> {};
+struct nautical_mile_per_hour : derived_scaled_unit<nautical_mile_per_hour, dim_speed, nautical_mile, hour> {};
 struct knot : alias_unit<nautical_mile_per_hour, "kn"> {};
 
 #ifndef UNITS_NO_LITERALS
diff --git a/src/systems/si-fps/include/units/isq/si/fps/volume.h b/src/systems/si-fps/include/units/isq/si/fps/volume.h
index c1ca9c72..7df571e2 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/volume.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/volume.h
@@ -37,7 +37,7 @@ namespace units::isq::si::fps {
 struct cubic_foot : derived_unit<cubic_foot> {};
 struct dim_volume : isq::dim_volume<dim_volume, cubic_foot, dim_length> {};
 
-struct cubic_yard : derived_deduced_unit<cubic_yard, dim_volume, yard> {};
+struct cubic_yard : derived_scaled_unit<cubic_yard, dim_volume, yard> {};
 
 template<UnitOf<dim_volume> U, Representation Rep = double>
 using volume = quantity<dim_volume, U, Rep>;
diff --git a/src/systems/si-international/include/units/isq/si/international/area.h b/src/systems/si-international/include/units/isq/si/international/area.h
index ce30183c..40fdc533 100644
--- a/src/systems/si-international/include/units/isq/si/international/area.h
+++ b/src/systems/si-international/include/units/isq/si/international/area.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si::international {
 
-struct square_foot : derived_deduced_unit<square_foot, si::dim_area, si::international::foot> {};
+struct square_foot : derived_scaled_unit<square_foot, si::dim_area, si::international::foot> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si-international/include/units/isq/si/international/speed.h b/src/systems/si-international/include/units/isq/si/international/speed.h
index 3081dd91..84f2dbf1 100644
--- a/src/systems/si-international/include/units/isq/si/international/speed.h
+++ b/src/systems/si-international/include/units/isq/si/international/speed.h
@@ -34,9 +34,9 @@
 
 namespace units::isq::si::international {
 
-struct mile_per_hour : derived_deduced_unit<mile_per_hour, si::dim_speed, si::international::mile, si::hour> {};
+struct mile_per_hour : derived_scaled_unit<mile_per_hour, si::dim_speed, si::international::mile, si::hour> {};
 struct nautical_mile_per_hour :
-    derived_deduced_unit<nautical_mile_per_hour, si::dim_speed, si::international::nautical_mile, si::hour> {};
+    derived_scaled_unit<nautical_mile_per_hour, si::dim_speed, si::international::nautical_mile, si::hour> {};
 struct knot : alias_unit<nautical_mile_per_hour, "kn"> {};
 
 #ifndef UNITS_NO_LITERALS
diff --git a/src/systems/si-international/include/units/isq/si/international/volume.h b/src/systems/si-international/include/units/isq/si/international/volume.h
index f4a5e5d5..4a5fcbcd 100644
--- a/src/systems/si-international/include/units/isq/si/international/volume.h
+++ b/src/systems/si-international/include/units/isq/si/international/volume.h
@@ -35,7 +35,7 @@
 
 namespace units::isq::si::international {
 
-struct cubic_foot : derived_deduced_unit<cubic_foot, si::dim_volume, si::international::foot> {};
+struct cubic_foot : derived_scaled_unit<cubic_foot, si::dim_volume, si::international::foot> {};
 
 #ifndef UNITS_NO_LITERALS
 
diff --git a/src/systems/si/include/units/isq/si/area.h b/src/systems/si/include/units/isq/si/area.h
index f95dfc08..d430a38c 100644
--- a/src/systems/si/include/units/isq/si/area.h
+++ b/src/systems/si/include/units/isq/si/area.h
@@ -37,26 +37,26 @@ namespace units::isq::si {
 struct square_metre : derived_unit<square_metre> {};
 struct dim_area : isq::dim_area<dim_area, square_metre, dim_length> {};
 
-struct square_yoctometre : derived_deduced_unit<square_yoctometre, dim_area, yoctometre> {};
-struct square_zeptometre : derived_deduced_unit<square_zeptometre, dim_area, zeptometre> {};
-struct square_attometre : derived_deduced_unit<square_attometre, dim_area, attometre> {};
-struct square_femtometre : derived_deduced_unit<square_femtometre, dim_area, femtometre> {};
-struct square_picometre : derived_deduced_unit<square_picometre, dim_area, picometre> {};
-struct square_nanometre : derived_deduced_unit<square_nanometre, dim_area, nanometre> {};
-struct square_micrometre : derived_deduced_unit<square_micrometre, dim_area, micrometre> {};
-struct square_millimetre : derived_deduced_unit<square_millimetre, dim_area, millimetre> {};
-struct square_centimetre : derived_deduced_unit<square_centimetre, dim_area, centimetre> {};
-struct square_decimetre : derived_deduced_unit<square_decimetre, dim_area, decimetre> {};
-struct square_decametre : derived_deduced_unit<square_decametre, dim_area, decametre> {};
-struct square_hectometre : derived_deduced_unit<square_hectometre, dim_area, hectometre> {};
-struct square_kilometre : derived_deduced_unit<square_kilometre, dim_area, kilometre> {};
-struct square_megametre : derived_deduced_unit<square_megametre, dim_area, megametre> {};
-struct square_gigametre : derived_deduced_unit<square_gigametre, dim_area, gigametre> {};
-struct square_terametre : derived_deduced_unit<square_terametre, dim_area, terametre> {};
-struct square_petametre : derived_deduced_unit<square_petametre, dim_area, petametre> {};
-struct square_exametre : derived_deduced_unit<square_exametre, dim_area, exametre> {};
-struct square_zettametre : derived_deduced_unit<square_zettametre, dim_area, zettametre> {};
-struct square_yottametre : derived_deduced_unit<square_yottametre, dim_area, yottametre> {};
+struct square_yoctometre : derived_scaled_unit<square_yoctometre, dim_area, yoctometre> {};
+struct square_zeptometre : derived_scaled_unit<square_zeptometre, dim_area, zeptometre> {};
+struct square_attometre : derived_scaled_unit<square_attometre, dim_area, attometre> {};
+struct square_femtometre : derived_scaled_unit<square_femtometre, dim_area, femtometre> {};
+struct square_picometre : derived_scaled_unit<square_picometre, dim_area, picometre> {};
+struct square_nanometre : derived_scaled_unit<square_nanometre, dim_area, nanometre> {};
+struct square_micrometre : derived_scaled_unit<square_micrometre, dim_area, micrometre> {};
+struct square_millimetre : derived_scaled_unit<square_millimetre, dim_area, millimetre> {};
+struct square_centimetre : derived_scaled_unit<square_centimetre, dim_area, centimetre> {};
+struct square_decimetre : derived_scaled_unit<square_decimetre, dim_area, decimetre> {};
+struct square_decametre : derived_scaled_unit<square_decametre, dim_area, decametre> {};
+struct square_hectometre : derived_scaled_unit<square_hectometre, dim_area, hectometre> {};
+struct square_kilometre : derived_scaled_unit<square_kilometre, dim_area, kilometre> {};
+struct square_megametre : derived_scaled_unit<square_megametre, dim_area, megametre> {};
+struct square_gigametre : derived_scaled_unit<square_gigametre, dim_area, gigametre> {};
+struct square_terametre : derived_scaled_unit<square_terametre, dim_area, terametre> {};
+struct square_petametre : derived_scaled_unit<square_petametre, dim_area, petametre> {};
+struct square_exametre : derived_scaled_unit<square_exametre, dim_area, exametre> {};
+struct square_zettametre : derived_scaled_unit<square_zettametre, dim_area, zettametre> {};
+struct square_yottametre : derived_scaled_unit<square_yottametre, dim_area, yottametre> {};
 
 struct are : alias_unit<square_decametre, "a"> {};
 struct centiare : prefixed_alias_unit<square_metre, centi, are> {};
diff --git a/src/systems/si/include/units/isq/si/speed.h b/src/systems/si/include/units/isq/si/speed.h
index a2c3adc0..8bcc17b7 100644
--- a/src/systems/si/include/units/isq/si/speed.h
+++ b/src/systems/si/include/units/isq/si/speed.h
@@ -37,7 +37,7 @@ namespace units::isq::si {
 struct metre_per_second : derived_unit<metre_per_second> {};
 struct dim_speed : isq::dim_speed<dim_speed, metre_per_second, dim_length, dim_time> {};
 
-struct kilometre_per_hour : derived_deduced_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
+struct kilometre_per_hour : derived_scaled_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
 
 template<UnitOf<dim_speed> U, Representation Rep = double>
 using speed = quantity<dim_speed, U, Rep>;
diff --git a/src/systems/si/include/units/isq/si/volume.h b/src/systems/si/include/units/isq/si/volume.h
index d85c4f43..1f61d874 100644
--- a/src/systems/si/include/units/isq/si/volume.h
+++ b/src/systems/si/include/units/isq/si/volume.h
@@ -37,26 +37,26 @@ namespace units::isq::si {
 struct cubic_metre : derived_unit<cubic_metre> {};
 struct dim_volume : isq::dim_volume<dim_volume, cubic_metre, dim_length> {};
 
-struct cubic_yoctometre : derived_deduced_unit<cubic_yoctometre, dim_volume, yoctometre> {};
-struct cubic_zeptometre : derived_deduced_unit<cubic_zeptometre, dim_volume, zeptometre> {};
-struct cubic_attometre : derived_deduced_unit<cubic_attometre, dim_volume, attometre> {};
-struct cubic_femtometre : derived_deduced_unit<cubic_femtometre, dim_volume, femtometre> {};
-struct cubic_picometre : derived_deduced_unit<cubic_picometre, dim_volume, picometre> {};
-struct cubic_nanometre : derived_deduced_unit<cubic_nanometre, dim_volume, nanometre> {};
-struct cubic_micrometre : derived_deduced_unit<cubic_micrometre, dim_volume, micrometre> {};
-struct cubic_millimetre : derived_deduced_unit<cubic_millimetre, dim_volume, millimetre> {};
-struct cubic_centimetre : derived_deduced_unit<cubic_centimetre, dim_volume, centimetre> {};
-struct cubic_decimetre : derived_deduced_unit<cubic_decimetre, dim_volume, decimetre> {};
-struct cubic_decametre : derived_deduced_unit<cubic_decametre, dim_volume, decametre> {};
-struct cubic_hectometre : derived_deduced_unit<cubic_hectometre, dim_volume, hectometre> {};
-struct cubic_kilometre : derived_deduced_unit<cubic_kilometre, dim_volume, kilometre> {};
-struct cubic_megametre : derived_deduced_unit<cubic_megametre, dim_volume, megametre> {};
-struct cubic_gigametre : derived_deduced_unit<cubic_gigametre, dim_volume, gigametre> {};
-struct cubic_terametre : derived_deduced_unit<cubic_terametre, dim_volume, terametre> {};
-struct cubic_petametre : derived_deduced_unit<cubic_petametre, dim_volume, petametre> {};
-struct cubic_exametre : derived_deduced_unit<cubic_exametre, dim_volume, exametre> {};
-struct cubic_zettametre : derived_deduced_unit<cubic_zettametre, dim_volume, zettametre> {};
-struct cubic_yottametre : derived_deduced_unit<cubic_yottametre, dim_volume, yottametre> {};
+struct cubic_yoctometre : derived_scaled_unit<cubic_yoctometre, dim_volume, yoctometre> {};
+struct cubic_zeptometre : derived_scaled_unit<cubic_zeptometre, dim_volume, zeptometre> {};
+struct cubic_attometre : derived_scaled_unit<cubic_attometre, dim_volume, attometre> {};
+struct cubic_femtometre : derived_scaled_unit<cubic_femtometre, dim_volume, femtometre> {};
+struct cubic_picometre : derived_scaled_unit<cubic_picometre, dim_volume, picometre> {};
+struct cubic_nanometre : derived_scaled_unit<cubic_nanometre, dim_volume, nanometre> {};
+struct cubic_micrometre : derived_scaled_unit<cubic_micrometre, dim_volume, micrometre> {};
+struct cubic_millimetre : derived_scaled_unit<cubic_millimetre, dim_volume, millimetre> {};
+struct cubic_centimetre : derived_scaled_unit<cubic_centimetre, dim_volume, centimetre> {};
+struct cubic_decimetre : derived_scaled_unit<cubic_decimetre, dim_volume, decimetre> {};
+struct cubic_decametre : derived_scaled_unit<cubic_decametre, dim_volume, decametre> {};
+struct cubic_hectometre : derived_scaled_unit<cubic_hectometre, dim_volume, hectometre> {};
+struct cubic_kilometre : derived_scaled_unit<cubic_kilometre, dim_volume, kilometre> {};
+struct cubic_megametre : derived_scaled_unit<cubic_megametre, dim_volume, megametre> {};
+struct cubic_gigametre : derived_scaled_unit<cubic_gigametre, dim_volume, gigametre> {};
+struct cubic_terametre : derived_scaled_unit<cubic_terametre, dim_volume, terametre> {};
+struct cubic_petametre : derived_scaled_unit<cubic_petametre, dim_volume, petametre> {};
+struct cubic_exametre : derived_scaled_unit<cubic_exametre, dim_volume, exametre> {};
+struct cubic_zettametre : derived_scaled_unit<cubic_zettametre, dim_volume, zettametre> {};
+struct cubic_yottametre : derived_scaled_unit<cubic_yottametre, dim_volume, yottametre> {};
 
 struct litre : alias_unit<cubic_decimetre, "l"> {};
 struct yoctolitre : prefixed_alias_unit<cubic_nanometre, yocto, litre> {};
diff --git a/test/unit_test/runtime/fmt_test.cpp b/test/unit_test/runtime/fmt_test.cpp
index 78cb6a25..4e24c5cd 100644
--- a/test/unit_test/runtime/fmt_test.cpp
+++ b/test/unit_test/runtime/fmt_test.cpp
@@ -189,7 +189,7 @@ TEST_CASE("operator<< on a quantity", "[text][ostream][fmt]")
       SECTION("surface tension")
       {
         struct newton_per_centimetre :
-            derived_deduced_unit<newton_per_centimetre, si::dim_surface_tension, newton, centimetre> {};
+            derived_scaled_unit<newton_per_centimetre, si::dim_surface_tension, newton, centimetre> {};
         const surface_tension<newton_per_centimetre> q(123);
         os << q;
 
diff --git a/test/unit_test/static/custom_unit_test.cpp b/test/unit_test/static/custom_unit_test.cpp
index bf26b340..474249fb 100644
--- a/test/unit_test/static/custom_unit_test.cpp
+++ b/test/unit_test/static/custom_unit_test.cpp
@@ -73,7 +73,7 @@ struct kilogram_per_second : derived_unit<kilogram_per_second> {};
 struct dim_mass_rate :
     derived_dimension<dim_mass_rate, kilogram_per_second, units::exponent<dim_mass, 1>, units::exponent<dim_time, -1>> {
 };
-struct kilogram_per_hour : derived_deduced_unit<kilogram_per_hour, dim_mass_rate, kilogram, hour> {};
+struct kilogram_per_hour : derived_scaled_unit<kilogram_per_hour, dim_mass_rate, kilogram, hour> {};
 [[maybe_unused]] constexpr auto a = 1_q_kg / 1_q_h;
 
 }  // namespace
diff --git a/test/unit_test/static/unit_test.cpp b/test/unit_test/static/unit_test.cpp
index 6a22b013..9ec78e22 100644
--- a/test/unit_test/static/unit_test.cpp
+++ b/test/unit_test/static/unit_test.cpp
@@ -55,7 +55,7 @@ static_assert([]<Prefix P>(P) {
 struct metre_per_second : derived_unit<metre_per_second> {};
 struct dim_speed :
     derived_dimension<dim_speed, metre_per_second, units::exponent<dim_length, 1>, units::exponent<dim_time, -1>> {};
-struct kilometre_per_hour : derived_deduced_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
+struct kilometre_per_hour : derived_scaled_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
 
 static_assert(equivalent<metre::named_unit, metre>);
 static_assert(equivalent<metre::scaled_unit, metre>);

From 01271a90b60d93448d40455932dc33848710457d Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 16:28:14 +0200
Subject: [PATCH 47/68] docs: project documentation updated with the latest
 unit-related changes

---
 docs/_static/img/units.svg             | 247 ++++++++++++++-----------
 docs/framework/units.rst               | 103 ++++-------
 docs/reference/core/concepts.rst       |   9 +-
 docs/reference/core/types/prefixes.rst |   6 -
 docs/reference/core/types/units.rst    |   5 +-
 docs/use_cases/extensions.rst          |  44 ++---
 6 files changed, 206 insertions(+), 208 deletions(-)

diff --git a/docs/_static/img/units.svg b/docs/_static/img/units.svg
index 59002174..21a7388d 100644
--- a/docs/_static/img/units.svg
+++ b/docs/_static/img/units.svg
@@ -1,122 +1,157 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?><svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" contentScriptType="application/ecmascript" contentStyleType="text/css" height="619px" preserveAspectRatio="none" style="width:678px;height:619px;background:#FCFCFC;" version="1.1" viewBox="0 0 678 619" width="678px" zoomAndPan="magnify"><defs/><g><!--MD5=[197a77df23d290968e58c76a2239d979]
-cluster Unit--><a href="../../framework/units.html" target="_top" title="../../framework/units.html" xlink:actuate="onRequest" xlink:href="../../framework/units.html" xlink:show="new" xlink:title="../../framework/units.html" xlink:type="simple"><rect fill="#FCFCFC" height="606" style="stroke:#000000;stroke-width:1.5;" width="665" x="7" y="7"/><path d="M51,7 L51,16.2969 L41,26.2969 L7,26.2969 " fill="none" style="stroke:#000000;stroke-width:1.5;"/><text fill="#000000" font-family="sans-serif" font-size="14" font-weight="bold" lengthAdjust="spacing" textLength="34" x="10" y="20.9951">Unit</text></a><!--MD5=[fe9c23f38d3f164e458ed7686471f90d]
-class prefix_family--><a href="../../framework/units.html#prefixed-unit" target="_top" title="../../framework/units.html#prefixed-unit" xlink:actuate="onRequest" xlink:href="../../framework/units.html#prefixed-unit" xlink:show="new" xlink:title="../../framework/units.html#prefixed-unit" xlink:type="simple"><rect codeLine="11" fill="#F8F8F8" height="23.9688" id="prefix_family" style="stroke:#383838;stroke-width:1.5;" width="82" x="65" y="72"/><text fill="#000000" font-family="sans-serif" font-size="12" font-style="italic" lengthAdjust="spacing" textLength="76" x="68" y="88.1387">prefix_family</text></a><!--MD5=[2c438ee281b14598fe4adbd039a51ed9]
-class no_prefix--><a href="../../framework/units.html#named-scaled-units" target="_top" title="../../framework/units.html#named-scaled-units" xlink:actuate="onRequest" xlink:href="../../framework/units.html#named-scaled-units" xlink:show="new" xlink:title="../../framework/units.html#named-scaled-units" xlink:type="simple"><rect codeLine="12" fill="#F8F8F8" height="23.9688" id="no_prefix" style="stroke:#383838;stroke-width:1.5;" width="61" x="422" y="101"/><text fill="#000000" font-family="sans-serif" font-size="12" font-style="italic" lengthAdjust="spacing" textLength="55" x="425" y="117.1387">no_prefix</text></a><!--MD5=[8ec8902a0493db0501cc5ae48138d755]
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+                <text fill="#000000" font-family="sans-serif" font-size="14" font-style="italic" lengthAdjust="spacing" textLength="137" x="286.5" y="120.9951">named_scaled_unit</text>
+                <rect fill="#FCFCFC" height="15.9688" style="stroke:#000000;stroke-width:1.0;stroke-dasharray:2.0,2.0;" width="118" x="431.5" y="100" />
+                <text fill="#000000" font-family="sans-serif" font-size="12" font-style="italic" lengthAdjust="spacing" textLength="116" x="432.5" y="112.1387">Symbol, Ratio, Unit</text>
+            </g>
+        </a> <!--MD5=[5e57872b30d77ee0da3206dd3d117986]
+class named_unit-->
+        <a href="../../framework/units.html#base-units" target="_top" title="../../framework/units.html#base-units" xlink:actuate="onRequest" xlink:href="../../framework/units.html#base-units" xlink:show="new" xlink:title="../../framework/units.html#base-units" xlink:type="simple">
+            <g id="elem_named_unit">
+                <rect codeLine="20" fill="#F1F1F1" height="26.2969" id="named_unit" rx="2.5" ry="2.5" style="stroke:#181818;stroke-width:0.5;" width="139" x="345.5" y="42" />
+                <text fill="#000000" font-family="sans-serif" font-size="14" font-style="italic" lengthAdjust="spacing" textLength="84" x="348.5" y="59.9951">named_unit</text>
+                <rect fill="#FCFCFC" height="15.9688" style="stroke:#000000;stroke-width:1.0;stroke-dasharray:2.0,2.0;" width="47" x="440.5" y="39" />
+                <text fill="#000000" font-family="sans-serif" font-size="12" font-style="italic" lengthAdjust="spacing" textLength="45" x="441.5" y="51.1387">Symbol</text>
+            </g>
+        </a> <!--MD5=[d10f3427b03caf67d8b4e569e5f4936e]
+reverse link scaled_unit to named_unit-->
+        <g id="link_scaled_unit_named_unit">
+            <path codeLine="22" d="M133.027,208.194 C158.437,172.883 205.676,115.067 261,85 C286.686,71.041 317.93,63.52 345.471,59.49 " fill="none" id="scaled_unit-backto-named_unit" style="stroke:#181818;stroke-width:1.0;" />
+            <polygon fill="none" points="138.679,212.326,121.521,224.76,127.181,204.34,138.679,212.326" style="stroke:#181818;stroke-width:1.0;" />
+        </g> <!--MD5=[c4573f7b87c3262f7d3adc92106a39ed]
+reverse link scaled_unit to named_scaled_unit-->
+        <g id="link_scaled_unit_named_scaled_unit">
+            <path codeLine="23" d="M145.911,212.637 C174.734,191.666 218.536,162.71 261,146 C279.262,138.814 299.451,133.292 319.011,129.068 " fill="none" id="scaled_unit-backto-named_scaled_unit" style="stroke:#181818;stroke-width:1.0;" />
+            <polygon fill="none" points="149.884,218.407,129.672,224.769,141.505,207.191,149.884,218.407" style="stroke:#181818;stroke-width:1.0;" />
+        </g> <!--MD5=[65b74da07c0359a7bcc888d9c9b6e7d5]
+reverse link scaled_unit to prefixed_unit-->
+        <g id="link_scaled_unit_prefixed_unit">
+            <path codeLine="24" d="M194.254,220.784 C215.93,216.246 239.344,211.391 261,207 C288.988,201.325 319.892,195.233 346.556,190.03 " fill="none" id="scaled_unit-backto-prefixed_unit" style="stroke:#181818;stroke-width:1.0;" />
+            <polygon fill="none" points="195.542,227.667,174.53,224.927,192.664,213.966,195.542,227.667" style="stroke:#181818;stroke-width:1.0;" />
+        </g> <!--MD5=[29a2e6b65a8256359df6b41e4d3b7c7c]
+reverse link scaled_unit to derived_unit-->
+        <g id="link_scaled_unit_derived_unit">
+            <path codeLine="25" d="M221.579,238 C271.79,238 328.764,238 367.604,238 " fill="none" id="scaled_unit-backto-derived_unit" style="stroke:#181818;stroke-width:1.0;" />
+            <polygon fill="none" points="221.276,245,201.276,238,221.276,231,221.276,245" style="stroke:#181818;stroke-width:1.0;" />
+        </g> <!--MD5=[1916bf928027667941dfca121ed1aff3]
+reverse link scaled_unit to derived_scaled_unit-->
+        <g id="link_scaled_unit_derived_deduced_unit">
+            <path codeLine="26" d="M197.3,255.089 C218.121,259.31 240.369,263.819 261,268 C290.086,273.894 322.282,280.418 349.606,285.954 " fill="none" id="scaled_unit-backto-derived_scaled_unit" style="stroke:#181818;stroke-width:1.0;" />
+            <polygon fill="none" points="195.683,261.904,177.472,251.07,198.464,248.183,195.683,261.904" style="stroke:#181818;stroke-width:1.0;" />
+        </g> <!--MD5=[19d99332ae619b76851ceaa34f4e9014]
+reverse link scaled_unit to alias_unit-->
+        <g id="link_scaled_unit_alias_unit">
+            <path codeLine="27" d="M145.982,263.005 C174.849,283.698 218.676,312.311 261,329 C285.078,338.494 312.484,345.219 337.384,349.919 " fill="none" id="scaled_unit-backto-alias_unit" style="stroke:#181818;stroke-width:1.0;" />
+            <polygon fill="none" points="141.677,268.529,129.714,251.039,149.972,257.251,141.677,268.529" style="stroke:#181818;stroke-width:1.0;" />
+        </g> <!--MD5=[a61d68e6008f4d1392d92030b50774f1]
+reverse link scaled_unit to prefixed_alias_unit-->
+        <g id="link_scaled_unit_prefixed_alias_unit">
+            <path codeLine="28" d="M133.104,267.552 C158.592,302.572 205.908,359.952 261,390 C275.157,397.7215 290.998,403.5283 306.976,407.8934 " fill="none" id="scaled_unit-backto-prefixed_alias_unit" style="stroke:#181818;stroke-width:1.0;" />
+            <polygon fill="none" points="127.332,271.513,121.559,251.125,138.786,263.462,127.332,271.513" style="stroke:#181818;stroke-width:1.0;" />
+        </g> <!--MD5=[f18d7856f7539404df991684234dc7ed]
 @startuml
 skinparam monochrome true
-skinparam shadowing false
-skinparam backgroundColor #fcfcfc
+    skinparam shadowing false
+    skinparam backgroundColor #fcfcfc
 
-hide members
-hide circle
+    hide members
+    hide circle
 
-left to right direction
+    left to right direction
 
-package Unit <<Frame>> [[../../framework/units.html]] {
-  abstract prefix_family [[../../framework/units.html#prefixed-unit]]
-  abstract no_prefix [[../../framework/units.html#named-scaled-units]]
-  abstract prefix<PrefixFamily, Symbol, Ratio> [[../../framework/units.html#prefixed-unit]]
+    package Unit <<Frame>> [[../../framework/units.html]] {
 
-  prefix_family <|- - no_prefix
-  prefix_family <.. prefix
+    abstract scaled_unit<UnitRatio, Unit>
 
-'  prefix_family <.. named_unit
-'  prefix_family <.. named_scaled_unit
-'  prefix_family <.. named_derived_unit
-'  prefix_family <.. alias_unit
+    abstract prefixed_alias_unit<Unit, Prefix, AliasUnit> [[../../framework/units.html#aliased-units]]
+    abstract alias_unit<Unit, Symbol> [[../../framework/units.html#aliased-units]]
+    abstract derived_scaled_unit<Dimension, Unit, Unit...> [[../../framework/units.html#derived-scaled-units]]
+    abstract derived_unit [[../../framework/units.html#derived-unnamed-units]]
+    abstract prefixed_unit<Prefix, Unit> [[../../framework/units.html#prefixed-unit]]
+    abstract named_scaled_unit<Symbol, Ratio, Unit> [[../../framework/units.html#named-scaled-units]]
+    abstract named_unit<Symbol> [[../../framework/units.html#base-units]]
 
-'  prefix <.. prefixed_unit
-'  prefix <.. prefixed_alias_unit
-
-  abstract scaled_unit<UnitRatio, Unit>
-
-  abstract prefixed_alias_unit<Unit, Prefix, AliasUnit> [[../../framework/units.html#aliased-units]]
-  abstract alias_unit<Unit, Symbol, PrefixFamily> [[../../framework/units.html#aliased-units]]
-  abstract named_derived_unit<Dimension, Symbol, PrefixFamily, Unit, Unit...> [[../../framework/units.html#derived-scaled-units]]
-  abstract derived_unit<Dimension, Unit, Unit...> [[../../framework/units.html#derived-scaled-units]]
-  abstract prefixed_unit<Prefix, Unit> [[../../framework/units.html#prefixed-unit]]
-  abstract named_scaled_unit<Symbol, PrefixFamily, Ratio, Unit> [[../../framework/units.html#named-scaled-units]]
-  abstract named_unit<Symbol, PrefixFamily> [[../../framework/units.html#base-units]]
-  abstract unit [[../../framework/units.html#derived-unnamed-units]]
-
-  scaled_unit <|- - unit
-  scaled_unit <|- - named_unit
-  scaled_unit <|- - named_scaled_unit
-  scaled_unit <|- - prefixed_unit
-  scaled_unit <|- - derived_unit
-  scaled_unit <|- - named_derived_unit
-  scaled_unit <|- - alias_unit
-  scaled_unit <|- - prefixed_alias_unit
-}
+    scaled_unit <|- - named_unit
+    scaled_unit <|- - named_scaled_unit
+    scaled_unit <|- - prefixed_unit
+    scaled_unit <|- - derived_unit
+    scaled_unit <|- - derived_scaled_unit
+    scaled_unit <|- - alias_unit
+    scaled_unit <|- - prefixed_alias_unit
+    }
 @enduml
 
-@startuml
-skinparam monochrome true
-skinparam shadowing false
-skinparam backgroundColor #fcfcfc
-
-hide members
-hide circle
-
-left to right direction
-
-package Unit <<Frame>> [[../../framework/units.html]] {
-  abstract prefix_family [[../../framework/units.html#prefixed-unit]]
-  abstract no_prefix [[../../framework/units.html#named-scaled-units]]
-  abstract prefix<PrefixFamily, Symbol, Ratio> [[../../framework/units.html#prefixed-unit]]
-
-  prefix_family <|- - no_prefix
-  prefix_family <.. prefix
-
-
-
-  abstract scaled_unit<UnitRatio, Unit>
-
-  abstract prefixed_alias_unit<Unit, Prefix, AliasUnit> [[../../framework/units.html#aliased-units]]
-  abstract alias_unit<Unit, Symbol, PrefixFamily> [[../../framework/units.html#aliased-units]]
-  abstract named_derived_unit<Dimension, Symbol, PrefixFamily, Unit, Unit...> [[../../framework/units.html#derived-scaled-units]]
-  abstract derived_unit<Dimension, Unit, Unit...> [[../../framework/units.html#derived-scaled-units]]
-  abstract prefixed_unit<Prefix, Unit> [[../../framework/units.html#prefixed-unit]]
-  abstract named_scaled_unit<Symbol, PrefixFamily, Ratio, Unit> [[../../framework/units.html#named-scaled-units]]
-  abstract named_unit<Symbol, PrefixFamily> [[../../framework/units.html#base-units]]
-  abstract unit [[../../framework/units.html#derived-unnamed-units]]
-
-  scaled_unit <|- - unit
-  scaled_unit <|- - named_unit
-  scaled_unit <|- - named_scaled_unit
-  scaled_unit <|- - prefixed_unit
-  scaled_unit <|- - derived_unit
-  scaled_unit <|- - named_derived_unit
-  scaled_unit <|- - alias_unit
-  scaled_unit <|- - prefixed_alias_unit
-}
-@enduml
-
-PlantUML version 1.2021.12(Tue Oct 05 16:01:58 UTC 2021)
+PlantUML version 1.2022.5(Sat Apr 30 10:55:52 UTC 2022)
 (GPL source distribution)
 Java Runtime: Java(TM) SE Runtime Environment
 JVM: Java HotSpot(TM) 64-Bit Server VM
 Default Encoding: UTF-8
 Language: en
 Country: US
---></g></svg>
+-->
+    </g>
+</svg>
\ No newline at end of file
diff --git a/docs/framework/units.rst b/docs/framework/units.rst
index 9e00b7ee..8e37e3e2 100644
--- a/docs/framework/units.rst
+++ b/docs/framework/units.rst
@@ -40,38 +40,22 @@ of a `scaled_unit` class template:
     left to right direction
 
     package Unit <<Frame>> [[../../framework/units.html]] {
-    abstract prefix_family [[../../framework/units.html#prefixed-unit]]
-    abstract no_prefix [[../../framework/units.html#named-scaled-units]]
-    abstract prefix<PrefixFamily, Symbol, Ratio> [[../../framework/units.html#prefixed-unit]]
-
-    prefix_family <|-- no_prefix
-    prefix_family <.. prefix
-
-    '  prefix_family <.. named_unit
-    '  prefix_family <.. named_scaled_unit
-    '  prefix_family <.. named_derived_unit
-    '  prefix_family <.. alias_unit
-
-    '  prefix <.. prefixed_unit
-    '  prefix <.. prefixed_alias_unit
 
     abstract scaled_unit<UnitRatio, Unit>
 
     abstract prefixed_alias_unit<Unit, Prefix, AliasUnit> [[../../framework/units.html#aliased-units]]
-    abstract alias_unit<Unit, Symbol, PrefixFamily> [[../../framework/units.html#aliased-units]]
-    abstract named_derived_unit<Dimension, Symbol, PrefixFamily, Unit, Unit...> [[../../framework/units.html#derived-scaled-units]]
-    abstract derived_unit<Dimension, Unit, Unit...> [[../../framework/units.html#derived-scaled-units]]
+    abstract alias_unit<Unit, Symbol> [[../../framework/units.html#aliased-units]]
+    abstract derived_scaled_unit<Dimension, Unit, Unit...> [[../../framework/units.html#derived-scaled-units]]
+    abstract derived_unit [[../../framework/units.html#derived-unnamed-units]]
     abstract prefixed_unit<Prefix, Unit> [[../../framework/units.html#prefixed-unit]]
-    abstract named_scaled_unit<Symbol, PrefixFamily, Ratio, Unit> [[../../framework/units.html#named-scaled-units]]
-    abstract named_unit<Symbol, PrefixFamily> [[../../framework/units.html#base-units]]
-    abstract unit [[../../framework/units.html#derived-unnamed-units]]
+    abstract named_scaled_unit<Symbol, Ratio, Unit> [[../../framework/units.html#named-scaled-units]]
+    abstract named_unit<Symbol> [[../../framework/units.html#base-units]]
 
-    scaled_unit <|-- unit
     scaled_unit <|-- named_unit
     scaled_unit <|-- named_scaled_unit
     scaled_unit <|-- prefixed_unit
     scaled_unit <|-- derived_unit
-    scaled_unit <|-- named_derived_unit
+    scaled_unit <|-- derived_scaled_unit
     scaled_unit <|-- alias_unit
     scaled_unit <|-- prefixed_alias_unit
     }
@@ -191,14 +175,11 @@ Those units are the scaled versions of a time dimension's base unit,
 namely second. Those can be defined easily in the library using
 `named_scaled_unit` class template::
 
-    struct minute : named_scaled_unit<minute, "min", no_prefix, ratio(60), second> {};
-    struct hour : named_scaled_unit<hour, "h", no_prefix, ratio(60), minute> {};
-    struct day : named_scaled_unit<day, "d", no_prefix, ratio(24), hour> {};
+    struct minute : named_scaled_unit<minute, "min", ratio(60), second> {};
+    struct hour : named_scaled_unit<hour, "h", ratio(60), minute> {};
+    struct day : named_scaled_unit<day, "d", ratio(24), hour> {};
 
-where `no_prefix` is a special tag type describing that the library should
-not allow to define a new prefixed unit that would use this unit as a
-reference ("kilohours" does not have much sense, right?). The `ratio` type
-used in the definition is really similar to ``std::ratio`` but it takes
+The `ratio` type used in the definition is really similar to ``std::ratio`` but it takes
 an additional ``Exponent`` template parameter that defines the exponent of the ratio.
 Another important difference is the fact that the objects of that class are used
 as class NTTPs rather then a type template parameter kind.
@@ -227,28 +208,26 @@ complete list of all the :term:`SI` prefixes supported by the library::
 
     namespace si {
 
-    struct prefix : prefix_family {};
-
-    struct yocto  : units::prefix<yocto,  prefix, "y",  ratio(1, 1, -24)> {};
-    struct zepto  : units::prefix<zepto,  prefix, "z",  ratio(1, 1, -21)> {};
-    struct atto   : units::prefix<atto,   prefix, "a",  ratio(1, 1, -18)> {};
-    struct femto  : units::prefix<femto,  prefix, "f",  ratio(1, 1, -15)> {};
-    struct pico   : units::prefix<pico,   prefix, "p",  ratio(1, 1, -12)> {};
-    struct nano   : units::prefix<nano,   prefix, "n",  ratio(1, 1,  -9)> {};
-    struct micro  : units::prefix<micro,  prefix, "µ",  ratio(1, 1,  -6)> {};
-    struct milli  : units::prefix<milli,  prefix, "m",  ratio(1, 1,  -3)> {};
-    struct centi  : units::prefix<centi,  prefix, "c",  ratio(1, 1,  -2)> {};
-    struct deci   : units::prefix<deci,   prefix, "d",  ratio(1, 1,  -1)> {};
-    struct deca   : units::prefix<deca,   prefix, "da", ratio(1, 1,   1)> {};
-    struct hecto  : units::prefix<hecto,  prefix, "h",  ratio(1, 1,   2)> {};
-    struct kilo   : units::prefix<kilo,   prefix, "k",  ratio(1, 1,   3)> {};
-    struct mega   : units::prefix<mega,   prefix, "M",  ratio(1, 1,   6)> {};
-    struct giga   : units::prefix<giga,   prefix, "G",  ratio(1, 1,   9)> {};
-    struct tera   : units::prefix<tera,   prefix, "T",  ratio(1, 1,  12)> {};
-    struct peta   : units::prefix<peta,   prefix, "P",  ratio(1, 1,  15)> {};
-    struct exa    : units::prefix<exa,    prefix, "E",  ratio(1, 1,  18)> {};
-    struct zetta  : units::prefix<zetta,  prefix, "Z",  ratio(1, 1,  21)> {};
-    struct yotta  : units::prefix<yotta,  prefix, "Y",  ratio(1, 1,  24)> {};
+    struct yocto : units::prefix<yocto, "y", ratio(1, 1, -24)> {};
+    struct zepto : units::prefix<zepto, "z", ratio(1, 1, -21)> {};
+    struct atto  : units::prefix<atto,  "a", ratio(1, 1, -18)> {};
+    struct femto : units::prefix<femto, "f", ratio(1, 1, -15)> {};
+    struct pico  : units::prefix<pico,  "p", ratio(1, 1, -12)> {};
+    struct nano  : units::prefix<nano,  "n", ratio(1, 1,  -9)> {};
+    struct micro : units::prefix<micro, "µ", ratio(1, 1,  -6)> {};
+    struct milli : units::prefix<milli, "m", ratio(1, 1,  -3)> {};
+    struct centi : units::prefix<centi, "c", ratio(1, 1,  -2)> {};
+    struct deci  : units::prefix<deci,  "d", ratio(1, 1,  -1)> {};
+    struct deca  : units::prefix<deca,  "da",ratio(1, 1,   1)> {};
+    struct hecto : units::prefix<hecto, "h", ratio(1, 1,   2)> {};
+    struct kilo  : units::prefix<kilo,  "k", ratio(1, 1,   3)> {};
+    struct mega  : units::prefix<mega,  "M", ratio(1, 1,   6)> {};
+    struct giga  : units::prefix<giga,  "G", ratio(1, 1,   9)> {};
+    struct tera  : units::prefix<tera,  "T", ratio(1, 1,  12)> {};
+    struct peta  : units::prefix<peta,  "P", ratio(1, 1,  15)> {};
+    struct exa   : units::prefix<exa,   "E", ratio(1, 1,  18)> {};
+    struct zetta : units::prefix<zetta, "Z", ratio(1, 1,  21)> {};
+    struct yotta : units::prefix<yotta, "Y", ratio(1, 1,  24)> {};
 
     }
 
@@ -257,14 +236,12 @@ domain::
 
     namespace iec80000 {
 
-    struct binary_prefix : prefix_family {};
-
-    struct kibi : units::prefix<kibi, binary_prefix, "Ki", ratio(                    1'024)> {};
-    struct mebi : units::prefix<mebi, binary_prefix, "Mi", ratio(                1'048'576)> {};
-    struct gibi : units::prefix<gibi, binary_prefix, "Gi", ratio(            1'073'741'824)> {};
-    struct tebi : units::prefix<tebi, binary_prefix, "Ti", ratio(        1'099'511'627'776)> {};
-    struct pebi : units::prefix<pebi, binary_prefix, "Pi", ratio(    1'125'899'906'842'624)> {};
-    struct exbi : units::prefix<exbi, binary_prefix, "Ei", ratio(1'152'921'504'606'846'976)> {};
+    struct kibi : units::prefix<kibi, "Ki", ratio(                    1'024)> {};
+    struct mebi : units::prefix<mebi, "Mi", ratio(                1'048'576)> {};
+    struct gibi : units::prefix<gibi, "Gi", ratio(            1'073'741'824)> {};
+    struct tebi : units::prefix<tebi, "Ti", ratio(        1'099'511'627'776)> {};
+    struct pebi : units::prefix<pebi, "Pi", ratio(    1'125'899'906'842'624)> {};
+    struct exbi : units::prefix<exbi, "Ei", ratio(1'152'921'504'606'846'976)> {};
 
     }
 
@@ -338,7 +315,7 @@ will result in a different unnamed unit symbol:
 
 where ``kilogram_metre_per_second`` is defined as::
 
-    struct kilogram_metre_per_second : unit<kilogram_metre_per_second> {};
+    struct kilogram_metre_per_second : derived_unit<kilogram_metre_per_second> {};
 
 However, the easiest way to define momentum is just to use the
 ``si::dim_speed`` derived dimension in the recipe:
@@ -385,12 +362,12 @@ ratio in reference to the "metre per second":
 
 Whichever, we choose there will always be someone not happy with our choice.
 
-Thanks to a `derived_unit` class template provided by the library this problem
+Thanks to a `derived_scaled_unit` class template provided by the library this problem
 does not exist at all. With it ``si::kilometre_per_hour`` can be defined as::
 
     namespace si {
 
-    struct kilometre_per_hour : derived_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
+    struct kilometre_per_hour : derived_scaled_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
 
     }
 
@@ -400,7 +377,7 @@ by him/her-self::
 
     namespace si::fps {
 
-    struct knot : named_derived_unit<knot, dim_speed, "knot", no_prefix, nautical_mile, hour> {};
+    struct knot : named_derived_unit<knot, dim_speed, "knot", nautical_mile, hour> {};
 
     }
 
diff --git a/docs/reference/core/concepts.rst b/docs/reference/core/concepts.rst
index ecc79b8a..99f38ce9 100644
--- a/docs/reference/core/concepts.rst
+++ b/docs/reference/core/concepts.rst
@@ -8,10 +8,6 @@ Concepts
     All names defined in this chapter reside in the :any:`units` namespace unless
     specified otherwise.
 
-.. concept:: template<typename T> PrefixFamily
-
-    A concept matching a prefix family. Satisfied by all types derived from :class:`prefix_family`.
-
 .. concept:: template<typename T> Prefix
 
     A concept matching a symbol prefix. Satisfied by all instantiations of :struct:`prefix`.
@@ -44,6 +40,11 @@ Concepts
     A concept matching all unit types in the library. Satisfied by all unit types derived
     from the instantiation of :class:`scaled_unit`.
 
+.. concept:: template<typename T> NamedUnit
+
+    A concept matching all unit types that have an atomic text symbol that can be used to aggregate it with
+    other named units to form a final symbol of a derived unit.
+
 .. concept:: template<typename U, typename D> UnitOf
 
     A concept matching only units of a specified dimension. Satisfied by all unit types that
diff --git a/docs/reference/core/types/prefixes.rst b/docs/reference/core/types/prefixes.rst
index 414eda66..7f160aef 100644
--- a/docs/reference/core/types/prefixes.rst
+++ b/docs/reference/core/types/prefixes.rst
@@ -1,11 +1,5 @@
 Prefixes
 ========
 
-.. doxygenstruct:: units::prefix_family
-   :members:
-
-.. doxygenstruct:: units::no_prefix
-   :members:
-
 .. doxygenstruct:: units::prefix
    :members:
diff --git a/docs/reference/core/types/units.rst b/docs/reference/core/types/units.rst
index 897fcc85..ce21fc68 100644
--- a/docs/reference/core/types/units.rst
+++ b/docs/reference/core/types/units.rst
@@ -4,9 +4,6 @@ Units
 .. doxygenstruct:: units::scaled_unit
    :members:
 
-.. doxygenstruct:: units::unit
-   :members:
-
 .. doxygenstruct:: units::named_unit
    :members:
 
@@ -19,7 +16,7 @@ Units
 .. doxygenstruct:: units::derived_unit
    :members:
 
-.. doxygenstruct:: units::named_derived_unit
+.. doxygenstruct:: units::derived_scaled_unit
    :members:
 
 .. doxygenstruct:: units::alias_unit
diff --git a/docs/use_cases/extensions.rst b/docs/use_cases/extensions.rst
index 9e07a92a..fd9db565 100644
--- a/docs/use_cases/extensions.rst
+++ b/docs/use_cases/extensions.rst
@@ -22,7 +22,7 @@ Defining a New Unit
 My working desk is of ``180 cm x 60 cm`` which gives an area of ``0.3 m²``. I would like to
 make it a unit of area for my project::
 
-    struct desk : named_scaled_unit<desk, "desk", no_prefix, ratio(3, 10), si::square_metre> {};
+    struct desk : named_scaled_unit<desk, "desk", ratio(3, 10), si::square_metre> {};
 
 With the above I can define a quantity with the area of ``2 desks``::
 
@@ -56,28 +56,22 @@ In case I would like to check how much area ``6 desks`` take in SI units::
 Enabling a Unit for Prefixing
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-In case I decide it is reasonable to express my desks with SI prefixes the only thing I have
-to change in the above code is to replace `no_prefix` with `isq::si::prefix`::
-
-    struct desk : named_scaled_unit<desk, "desk", si::prefix, ratio(3, 10), si::square_metre> {};
-
-Now I can define a new unit named ``kilodesk``::
+In case I decide it is reasonable to express my desks with SI prefixes, I can define
+a new unit named ``kilodesk``::
 
     struct kilodesk : prefixed_unit<kilodesk, si::kilo, desk> {};
     static_assert(3_d * 1000 == si::area<kilodesk>(3));
 
 But maybe SI prefixes are not good for me. Maybe I always pack ``6`` desks into one package
-for shipment and ``40`` such packages fit into my lorry. To express this with prefixes a new
-prefix family and prefixes are needed::
+for shipment and ``40`` such packages fit into my lorry. To express this new prefix definitions
+are needed::
 
-    struct shipping_prefix : prefix_family {};
-
-    struct package : prefix<package, shipping_prefix, "pkg", ratio(6)> {};
-    struct lorry : prefix<lorry, shipping_prefix, "lorry", ratio(6 * 40)> {};
+    struct package : prefix<package, "pkg", ratio(6)> {};
+    struct lorry : prefix<lorry, "lorry", ratio(6 * 40)> {};
 
 Now we can use it for our unit::
 
-    struct desk : named_scaled_unit<desk, "desk", shipping_prefix, ratio(3, 10), si::square_metre> {};
+    struct desk : named_scaled_unit<desk, "desk", ratio(3, 10), si::square_metre> {};
     struct packagedesk : prefixed_unit<packagedesk, package, desk> {};
     struct lorrydesk : prefixed_unit<lorrydesk, lorry, desk> {};
 
@@ -111,14 +105,14 @@ rate of wood during production I need to define a new derived dimension together
 coherent unit::
 
     // coherent unit must apply to the system rules (in this case SI)
-    struct square_metre_per_second : unit<square_metre_per_second> {};
+    struct square_metre_per_second : derived_unit<square_metre_per_second> {};
 
     // new derived dimensions
     struct dim_desk_rate : derived_dimension<dim_desk_rate, square_metre_per_second,
                                              exponent<si::dim_area, 1>, exponent<si::dim_time, -1>> {};
 
     // our unit of interest for a new derived dimension
-    struct desk_per_hour : derived_unit<desk_per_hour, dim_desk_rate, desk, si::hour> {};
+    struct desk_per_hour : derived_scaled_unit<desk_per_hour, dim_desk_rate, desk, si::hour> {};
 
     // a quantity of our dimension
     template<UnitOf<dim_desk_rate> U, Representation Rep = double>
@@ -147,7 +141,7 @@ a customer's office I would need a unit called ``person_per_desk`` of a new deri
 dimension. However, our library does not know what a ``person`` is. For this I need to
 define a new base dimension, its units, quantity helper, concept, and UDLs::
 
-    struct person : named_unit<person, "person", no_prefix> {};
+    struct person : named_unit<person, "person"> {};
     struct dim_people : base_dimension<"people", person> {};
 
     template<UnitOf<dim_people> U, Representation Rep = double>
@@ -162,12 +156,12 @@ define a new base dimension, its units, quantity helper, concept, and UDLs::
 
 With the above we can now define a new derived dimension::
 
-    struct person_per_square_metre : unit<person_per_square_metre> {};
+    struct person_per_square_metre : derived_unit<person_per_square_metre> {};
     struct dim_occupancy_rate : derived_dimension<dim_occupancy_rate, person_per_square_metre,
                                                   exponent<dim_people, 1>,
                                                   exponent<si::dim_area, -1>> {};
 
-    struct person_per_desk : derived_unit<person_per_desk, dim_occupancy_rate, person, desk> {};
+    struct person_per_desk : derived_scaled_unit<person_per_desk, dim_occupancy_rate, person, desk> {};
 
     template<UnitOf<dim_occupancy_rate> U, Representation Rep = double>
     using occupancy_rate = quantity<dim_occupancy_rate, U, Rep>;
@@ -211,8 +205,8 @@ Such units do not share their references with base units of other systems:
 
     namespace fps {
 
-    struct foot : named_unit<foot, "ft", no_prefix> {};
-    struct yard : named_scaled_unit<yard, "yd", no_prefix, ratio(3), foot> {};
+    struct foot : named_unit<foot, "ft"> {};
+    struct yard : named_scaled_unit<yard, "yd", ratio(3), foot> {};
 
     struct dim_length : base_dimension<"L", foot> {};
 
@@ -231,7 +225,7 @@ different systems:
 
     namespace si {
 
-    struct metre : named_unit<metre, "m", units::isq::si::prefix> {};
+    struct metre : named_unit<metre, "m"> {};
     struct kilometre : prefixed_unit<kilometre, units::isq::si::kilo, metre> {};
 
     struct dim_length : base_dimension<"L", metre> {};
@@ -241,8 +235,8 @@ different systems:
 
     namespace fps {
 
-    struct foot : named_scaled_unit<foot, "ft", no_prefix, ratio(3'048, 1'000, -1), metre> {};
-    struct yard : named_scaled_unit<yard, "yd", no_prefix, ratio(3), foot> {};
+    struct foot : named_scaled_unit<foot, "ft", ratio(3'048, 1'000, -1), metre> {};
+    struct yard : named_scaled_unit<yard, "yd", ratio(3), foot> {};
 
     struct dim_length : base_dimension<"L", foot> {};
 
@@ -300,7 +294,7 @@ the library always keeps the ratio relative to the primary reference unit
 which in this case is ``si::metre``. This results in much bigger ratios
 and in case of some units may result with a problem of limited resolution
 of ``std::int64_t`` used to store numerator, denominator, and exponent
-values of ratio. For example the ``si::fps::qubic_foot`` already has the
+values of ratio. For example the ``si::fps::cubic_foot`` already has the
 ratio of ``ratio{55306341, 1953125, -3}``. In case of more complicated
 conversion ratio we can overflow `ratio` and get a compile-time error.
 In such a situation the standalone system may be a better choice here.

From d9a16aa8079560d648ab42dd876464087c756b44 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 16:41:55 +0200
Subject: [PATCH 48/68] build: gsl-lite updated to 0.40.0

---
 conanfile.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/conanfile.py b/conanfile.py
index a0582e42..f16b547d 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -51,7 +51,7 @@ class MPUnitsConan(ConanFile):
     url = "https://github.com/mpusz/units"
     settings = "os", "compiler", "build_type", "arch"
     requires = (
-        "gsl-lite/0.38.1"
+        "gsl-lite/0.40.0"
     )
     options = {
         "downcast_mode": ["off", "on", "auto"],

From 4951e30fdd370daf05f553caa47c6c30eb418fc6 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 16:42:26 +0200
Subject: [PATCH 49/68] build: catch2 updated to 2.13.9

---
 conanfile.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/conanfile.py b/conanfile.py
index f16b547d..76021ceb 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -107,7 +107,7 @@ class MPUnitsConan(ConanFile):
 
     def build_requirements(self):
         if self._run_tests:
-            self.test_requires("catch2/2.13.7")
+            self.test_requires("catch2/2.13.9")
             self.test_requires("wg21-linear_algebra/0.7.2")
             if self.options.build_docs:
                 self.tool_requires("doxygen/1.9.2")

From 9a022da91948ad6d495a99765ff7b7ca2571948f Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 16:48:39 +0200
Subject: [PATCH 50/68] chore: SVG image fixed to make pre-commit happy

---
 docs/_static/img/units.svg | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/docs/_static/img/units.svg b/docs/_static/img/units.svg
index 21a7388d..c19aae88 100644
--- a/docs/_static/img/units.svg
+++ b/docs/_static/img/units.svg
@@ -1,7 +1,8 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" contentStyleType="text/css" height="456px" preserveAspectRatio="none" style="width:591px;height:456px;background:#FCFCFC;" version="1.1" viewBox="0 0 591 456" width="591px" zoomAndPan="magnify">
     <defs />
-    <g> <!--MD5=[197a77df23d290968e58c76a2239d979]
+    <g>
+        <!--MD5=[197a77df23d290968e58c76a2239d979]
 cluster Unit-->
         <g id="cluster_Unit">
             <a href="../../framework/units.html" target="_top" title="../../framework/units.html" xlink:actuate="onRequest" xlink:href="../../framework/units.html" xlink:show="new" xlink:title="../../framework/units.html" xlink:type="simple">
@@ -154,4 +155,4 @@ Language: en
 Country: US
 -->
     </g>
-</svg>
\ No newline at end of file
+</svg>

From 7737167d1dcf2f9bc1880d880c512729689aeef2 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 18:10:51 +0200
Subject: [PATCH 51/68] fix: unit symbol text output unit tests fixed

---
 src/core/include/units/bits/unit_text.h       | 28 +++++++++----------
 .../include/units/generic/dimensionless.h     |  2 +-
 src/core/include/units/unit.h                 |  3 ++
 3 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/src/core/include/units/bits/unit_text.h b/src/core/include/units/bits/unit_text.h
index a8c323e4..d0118397 100644
--- a/src/core/include/units/bits/unit_text.h
+++ b/src/core/include/units/bits/unit_text.h
@@ -26,6 +26,7 @@
 #include <units/bits/external/text_tools.h>
 #include <units/derived_dimension.h>
 #include <units/prefix.h>
+#include <units/unit.h>
 
 namespace units::detail {
 
@@ -57,7 +58,7 @@ constexpr auto ratio_text()
   }
 }
 
-template<ratio R, std::size_t SymbolLen>
+template<Unit U, ratio R, std::size_t SymbolLen>
 constexpr auto prefix_or_ratio_text()
 {
   if constexpr (R.num == 1 && R.den == 1 && R.exp == 0) {
@@ -67,7 +68,7 @@ constexpr auto prefix_or_ratio_text()
     // try to form a prefix
     using prefix = downcast<detail::prefix_base<R>>;
 
-    if constexpr (!is_same_v<prefix, prefix_base<R>>) {
+    if constexpr (can_be_prefixed<U> && !is_same_v<prefix, prefix_base<R>>) {
       // print as a prefixed unit
       return prefix::symbol;
     } else {
@@ -138,19 +139,16 @@ constexpr auto unit_text()
     // print as a prefix or ratio of a coherent unit
     using coherent_unit = dimension_unit<Dim>;
 
-    if constexpr (has_symbol<coherent_unit>) {
-      // use predefined coherent unit symbol
-      constexpr auto symbol_text = coherent_unit::symbol;
-      constexpr auto prefix_txt =
-        prefix_or_ratio_text<U::ratio / coherent_unit::ratio, symbol_text.standard().size()>();
-      return prefix_txt + symbol_text;
-    } else {
-      // use derived dimension ingredients to create a unit symbol
-      constexpr auto symbol_text = derived_dimension_unit_text<Dim>();
-      constexpr auto prefix_txt =
-        prefix_or_ratio_text<U::ratio / coherent_unit::ratio, symbol_text.standard().size()>();
-      return prefix_txt + symbol_text;
-    }
+    constexpr auto symbol_text = []() {
+      if constexpr (has_symbol<coherent_unit>)
+        return coherent_unit::symbol;
+      else
+        return derived_dimension_unit_text<Dim>();
+    }();
+
+    constexpr auto prefix_txt =
+      prefix_or_ratio_text<U, U::ratio / coherent_unit::ratio, symbol_text.standard().size()>();
+    return prefix_txt + symbol_text;
   }
 }
 
diff --git a/src/core/include/units/generic/dimensionless.h b/src/core/include/units/generic/dimensionless.h
index 562977fc..acf9e91d 100644
--- a/src/core/include/units/generic/dimensionless.h
+++ b/src/core/include/units/generic/dimensionless.h
@@ -30,7 +30,7 @@
 
 namespace units {
 
-struct one : named_unit<one, ""> {};
+struct one : derived_unit<one> {};
 struct percent : named_scaled_unit<percent, "%", ratio(1, 100), one> {};
 
 /**
diff --git a/src/core/include/units/unit.h b/src/core/include/units/unit.h
index 6e8ed3ca..eddb7ea2 100644
--- a/src/core/include/units/unit.h
+++ b/src/core/include/units/unit.h
@@ -225,6 +225,9 @@ void can_be_prefixed_impl(const volatile alias_unit<U, Symbol>*);
 template<Unit U>
 inline constexpr bool can_be_prefixed<U> = requires(U * u) { can_be_prefixed_impl(u); };
 
+template<ratio R, typename U>
+inline constexpr bool can_be_prefixed<scaled_unit<R, U>> = can_be_prefixed<typename U::reference>;
+
 }  // namespace detail
 
 }  // namespace units

From 6f665b2074c492b47431a3fa4fc6aca7cc9de5af Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 19:33:29 +0200
Subject: [PATCH 52/68] style: `ci-conan` reformatted

---
 .github/workflows/ci-conan.yml | 144 +++++++++++++++++++++------------
 1 file changed, 94 insertions(+), 50 deletions(-)

diff --git a/.github/workflows/ci-conan.yml b/.github/workflows/ci-conan.yml
index 9a4f3ecc..55024a62 100644
--- a/.github/workflows/ci-conan.yml
+++ b/.github/workflows/ci-conan.yml
@@ -25,10 +25,10 @@ name: Conan CI
 on:
   push:
     paths-ignore:
-    - 'docs/**'
+      - "docs/**"
   pull_request:
     paths-ignore:
-    - 'docs/**'
+      - "docs/**"
 
 jobs:
   build:
@@ -38,51 +38,95 @@ jobs:
       fail-fast: false
       matrix:
         config:
-        - {
-            name: "Windows MSVC 14.2",
-            os: windows-2019,
-            compiler: { type: VISUAL, version: 16, std: 20, cc: "cl", cxx: "cl" }
-          }
-        - {
-            name: "Windows MSVC 14.3",
-            os: windows-2022,
-            compiler: { type: MSVC, version: 193, std: 23, cc: "cl", cxx: "cl" }
-          }
-        - {
-            name: "Ubuntu GCC-10",
-            os: ubuntu-20.04,
-            compiler: { type: GCC, version: 10, cc: "gcc-10", cxx: "g++-10", std: 20 },
-            lib: "libstdc++11"
-          }
-        - {
-            name: "Ubuntu GCC-11",
-            os: ubuntu-20.04,
-            compiler: { type: GCC, version: 11, cc: "gcc-11", cxx: "g++-11", std: 20 },
-            lib: "libstdc++11"
-          }
-        - {
-            name: "Ubuntu Clang-12 + libstdc++11",
-            os: ubuntu-20.04,
-            compiler: { type: CLANG, version: 12, cc: "clang-12", cxx: "clang++-12", std: 20 },
-            lib: "libstdc++11"
-          }
-        - {
-            name: "Ubuntu Clang-12 + libc++",
-            os: ubuntu-20.04,
-            compiler: { type: CLANG, version: 12, cc: "clang-12", cxx: "clang++-12", std: 20 },
-            lib: "libc++"
-          }
-        - {
-            name: "Ubuntu Clang-13 + libc++",
-            os: ubuntu-20.04,
-            compiler: { type: CLANG, version: 13, cc: "clang-13", cxx: "clang++-13", std: 20 },
-            lib: "libc++"
-          }
-        - {
-            name: "MacOS Apple Clang 13",
-            os: macos-11,
-            compiler: { type: APPLE_CLANG, version: "13.0", cc: "clang", cxx: "clang++", std: 20 }
-          }
+          - {
+              name: "Windows MSVC 14.2",
+              os: windows-2019,
+              compiler:
+                { type: VISUAL, version: 16, std: 20, cc: "cl", cxx: "cl" },
+            }
+          - {
+              name: "Windows MSVC 14.3",
+              os: windows-2022,
+              compiler:
+                { type: MSVC, version: 193, std: 23, cc: "cl", cxx: "cl" },
+            }
+          - {
+              name: "Ubuntu GCC-10",
+              os: ubuntu-20.04,
+              compiler:
+                {
+                  type: GCC,
+                  version: 10,
+                  cc: "gcc-10",
+                  cxx: "g++-10",
+                  std: 20,
+                },
+              lib: "libstdc++11",
+            }
+          - {
+              name: "Ubuntu GCC-11",
+              os: ubuntu-20.04,
+              compiler:
+                {
+                  type: GCC,
+                  version: 11,
+                  cc: "gcc-11",
+                  cxx: "g++-11",
+                  std: 20,
+                },
+              lib: "libstdc++11",
+            }
+          - {
+              name: "Ubuntu Clang-12 + libstdc++11",
+              os: ubuntu-20.04,
+              compiler:
+                {
+                  type: CLANG,
+                  version: 12,
+                  cc: "clang-12",
+                  cxx: "clang++-12",
+                  std: 20,
+                },
+              lib: "libstdc++11",
+            }
+          - {
+              name: "Ubuntu Clang-12 + libc++",
+              os: ubuntu-20.04,
+              compiler:
+                {
+                  type: CLANG,
+                  version: 12,
+                  cc: "clang-12",
+                  cxx: "clang++-12",
+                  std: 20,
+                },
+              lib: "libc++",
+            }
+          - {
+              name: "Ubuntu Clang-13 + libc++",
+              os: ubuntu-20.04,
+              compiler:
+                {
+                  type: CLANG,
+                  version: 13,
+                  cc: "clang-13",
+                  cxx: "clang++-13",
+                  std: 20,
+                },
+              lib: "libc++",
+            }
+          - {
+              name: "MacOS Apple Clang 13",
+              os: macos-11,
+              compiler:
+                {
+                  type: APPLE_CLANG,
+                  version: "13.0",
+                  cc: "clang",
+                  cxx: "clang++",
+                  std: 20,
+                },
+            }
         # In case a Conan docker image will be needed to provide a specific configuration we can use a Docker image as follows
         # - {
         #     name: "Ubuntu GCC 10.2.0",
@@ -90,8 +134,8 @@ jobs:
         #     compiler: { type: GCC, version: 10, cc: "gcc-10", cxx: "g++-10" },
         #     docker_image: conanio/gcc10
         #   }
-        build_type: [ "Release", "Debug" ]
-        downcast_mode: [ "on", "auto" ]
+        build_type: ["Release", "Debug"]
+        downcast_mode: ["on", "auto"]
     steps:
       - uses: actions/checkout@v2
       - uses: hendrikmuhs/ccache-action@v1
@@ -141,7 +185,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v2
         with:
-          python-version: '3.8'
+          python-version: "3.8"
       - name: Install Conan Package Tools
         run: |
           pip install -U conan_package_tools

From 05a5c881f0e48ffd1659513687366e4fccf7829e Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 19:35:07 +0200
Subject: [PATCH 53/68] ci: clang-14 support added

---
 .github/workflows/ci-conan.yml              | 13 +++++++++++++
 .github/workflows/ci-test-package-cmake.yml |  7 +++++++
 2 files changed, 20 insertions(+)

diff --git a/.github/workflows/ci-conan.yml b/.github/workflows/ci-conan.yml
index 55024a62..0c1ad283 100644
--- a/.github/workflows/ci-conan.yml
+++ b/.github/workflows/ci-conan.yml
@@ -115,6 +115,19 @@ jobs:
                 },
               lib: "libc++",
             }
+          - {
+              name: "Ubuntu Clang-14 + libc++",
+              os: ubuntu-20.04,
+              compiler:
+                {
+                  type: CLANG,
+                  version: 14,
+                  cc: "clang-14",
+                  cxx: "clang++-14",
+                  std: 20,
+                },
+              lib: "libc++",
+            }
           - {
               name: "MacOS Apple Clang 13",
               os: macos-11,
diff --git a/.github/workflows/ci-test-package-cmake.yml b/.github/workflows/ci-test-package-cmake.yml
index 2337af7e..2c6440ac 100644
--- a/.github/workflows/ci-test-package-cmake.yml
+++ b/.github/workflows/ci-test-package-cmake.yml
@@ -80,6 +80,13 @@ jobs:
                 { type: CLANG, version: 13, cc: "clang-13", cxx: "clang++-13" },
               lib: "libc++",
             }
+          - {
+              name: "Ubuntu Clang 14.0.0 + libc++",
+              os: ubuntu-20.04,
+              compiler:
+                { type: CLANG, version: 14, cc: "clang-14", cxx: "clang++-14" },
+              lib: "libc++",
+            }
           - {
               name: "MacOS Apple Clang 13",
               os: macos-11,

From fddde2615707f099fc4cf6c213f2f98df800e00c Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 20:20:55 +0200
Subject: [PATCH 54/68] fix(example): clang-14 compilation fixed

---
 example/kalman_filter/kalman.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/example/kalman_filter/kalman.h b/example/kalman_filter/kalman.h
index 16a21375..a034d2db 100644
--- a/example/kalman_filter/kalman.h
+++ b/example/kalman_filter/kalman.h
@@ -84,7 +84,7 @@ public:
   uncertainty_type uncertainty;
 };
 
-#if UNITS_COMP_CLANG <= 13
+#if UNITS_COMP_CLANG <= 14
 
 template<QuantityOrQuantityPoint QQP, units::Quantity U>
 estimation(state<QQP>, U) -> estimation<QQP>;

From 0a11ebacb71f42c45ec6c463f1dfe779f4f2f322 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 20:21:44 +0200
Subject: [PATCH 55/68] chore(example): unused
 `example/literals/custom_systems.cpp` removed

---
 example/literals/custom_systems.cpp | 113 ----------------------------
 1 file changed, 113 deletions(-)
 delete mode 100644 example/literals/custom_systems.cpp

diff --git a/example/literals/custom_systems.cpp b/example/literals/custom_systems.cpp
deleted file mode 100644
index 403475e1..00000000
--- a/example/literals/custom_systems.cpp
+++ /dev/null
@@ -1,113 +0,0 @@
-// The MIT License (MIT)
-//
-// Copyright (c) 2018 Mateusz Pusz
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in all
-// copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-// SOFTWARE.
-
-#include <units/base_dimension.h>
-#include <units/isq/si/prefixes.h>
-#include <units/quantity.h>
-#include <units/quantity_io.h>
-#include <units/unit.h>
-#include <iostream>
-#include <type_traits>
-
-using namespace units;
-
-namespace fps {
-
-struct foot : named_unit<foot, "ft"> {};
-struct yard : named_scaled_unit<yard, "yd", ratio(3), foot> {};
-
-struct dim_length : base_dimension<"L", foot> {};
-
-template<UnitOf<dim_length> U, Representation Rep = double>
-using length = quantity<dim_length, U, Rep>;
-
-}  // namespace fps
-
-namespace si {
-
-struct metre : named_unit<metre, "m"> {};
-struct kilometre : prefixed_unit<kilometre, units::isq::si::kilo, metre> {};
-
-struct dim_length : base_dimension<"L", metre> {};
-
-template<UnitOf<dim_length> U, Representation Rep = double>
-using length = quantity<dim_length, U, Rep>;
-
-namespace fps {
-
-struct foot : named_scaled_unit<foot, "ft", ratio(3'048, 1'000, -1), metre> {};
-struct yard : named_scaled_unit<yard, "yd", ratio(3), foot> {};
-
-struct dim_length : base_dimension<"L", foot> {};
-
-template<UnitOf<dim_length> U, Representation Rep = double>
-using length = quantity<dim_length, U, Rep>;
-
-}  // namespace fps
-}  // namespace si
-
-void conversions()
-{
-  // constexpr auto fps_yard = fps::length<fps::yard>(1.);
-  // std::cout << quantity_cast<si::kilometre>(fps_yard) << "\n";
-
-  constexpr auto si_fps_yard = si::fps::length<si::fps::yard>(1.);
-  std::cout << quantity_cast<si::kilometre>(si_fps_yard) << "\n";
-}
-
-void unknown_dimensions()
-{
-  constexpr auto fps_yard = fps::length<fps::yard>(1.);
-  constexpr auto fps_area = quantity_cast<unknown_coherent_unit>(fps_yard * fps_yard);
-  std::cout << fps_yard << "\n";
-  std::cout << fps_area << "\n";
-
-  constexpr auto si_fps_yard = si::fps::length<si::fps::yard>(1.);
-  constexpr auto si_fps_area = quantity_cast<unknown_coherent_unit>(si_fps_yard * si_fps_yard);
-  std::cout << si_fps_yard << "\n";
-  std::cout << si_fps_area << "\n";
-}
-
-std::ostream& operator<<(std::ostream& os, const ratio& r)
-{
-  return os << "ratio{" << r.num << ", " << r.den << ", " << r.exp << "}";
-}
-
-template<Unit U>
-std::ostream& operator<<(std::ostream& os, const U& u)
-{
-  using unit_type = std::remove_cvref_t<decltype(u)>;
-  return os << unit_type::ratio << " x " << unit_type::reference::symbol.standard();
-}
-
-void what_is_your_ratio()
-{
-  std::cout << "fps:     " << fps::yard() << "\n";
-  std::cout << "si::fps: " << si::fps::yard() << "\n";
-}
-
-int main()
-{
-  conversions();
-  unknown_dimensions();
-  what_is_your_ratio();
-}

From 89a412593a7a7549e2946191da587daef883ab89 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 11 May 2022 20:22:44 +0200
Subject: [PATCH 56/68] docs: `wg21-linear_algebra` Conan repo URL changed to
 `https://conan.io/center/wg21-linear_algebra`

---
 docs/use_cases/linear_algebra.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/use_cases/linear_algebra.rst b/docs/use_cases/linear_algebra.rst
index 6cc017b0..bb3c1111 100644
--- a/docs/use_cases/linear_algebra.rst
+++ b/docs/use_cases/linear_algebra.rst
@@ -11,7 +11,7 @@ enough to be used with other Linear Algebra libraries existing on the market.
     All of the examples provided in this chapter refer to the official proposal of the
     Linear Algebra Library for the C++23 defined in `P1385 <https://wg21.link/P1385>`_
     and its latest implementation from `GitHub <https://github.com/BobSteagall/wg21/tree/master/include>`_
-    or `Conan <https://twonington.jfrog.io/artifactory/api/conan/conan-oss>`_.
+    or `Conan <https://conan.io/center/wg21-linear_algebra>`_.
     Also, to simplify the examples all of them assume::
 
         using namespace std::math;

From 08ceb4c8db48a677b09476cfed5a5a048ed6f2dd Mon Sep 17 00:00:00 2001
From: Markus Hofbauer <markus.hofbauer@tum.de>
Date: Thu, 12 May 2022 13:58:16 +0200
Subject: [PATCH 57/68] add python formatter

---
 .pre-commit-config.yaml | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 90919c87..dd44ca4c 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -2,7 +2,7 @@ default_stages: [commit]
 
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.1.0
+    rev: v4.2.0
     hooks:
       - id: trailing-whitespace
       - id: end-of-file-fixer
@@ -16,5 +16,10 @@ repos:
       - id: cmake-format
         additional_dependencies: ["cmakelang[YAML]"]
       # - id: cmake-lint
-      # additional_dependencies: ["cmakelang"]
-      # exclude: "cmake/.*"
+      #   additional_dependencies: ["cmakelang"]
+      #   exclude: "cmake/.*"
+  - repo: https://github.com/psf/black
+    rev: 22.3.0
+    hooks:
+      - id: black
+        language_version: python3

From 42072cc7c574d4b5b0072f00fe14c846e0f62e56 Mon Sep 17 00:00:00 2001
From: Markus Hofbauer <markus.hofbauer@tum.de>
Date: Thu, 12 May 2022 13:58:32 +0200
Subject: [PATCH 58/68] apply python format

---
 build.py     |  14 +-
 conanfile.py |  53 +++--
 docs/conf.py | 614 +++++++++++++++++++++++++++++++++++----------------
 3 files changed, 468 insertions(+), 213 deletions(-)

diff --git a/build.py b/build.py
index c733eb38..c397b944 100644
--- a/build.py
+++ b/build.py
@@ -31,16 +31,14 @@ from cpt.packager import ConanMultiPackager
 if __name__ == "__main__":
     builder = ConanMultiPackager(
         # package id
-        channel = "testing",
-        stable_branch_pattern = r"v\d+\.\d+\.\d+.*",
-
+        channel="testing",
+        stable_branch_pattern=r"v\d+\.\d+\.\d+.*",
         # dependencies
-        build_policy = ["mp-units", "outdated"],
-        upload_dependencies = "all",
-        pip_install = ["sphinx", "recommonmark", "breathe"],
-
+        build_policy=["mp-units", "outdated"],
+        upload_dependencies="all",
+        pip_install=["sphinx", "recommonmark", "breathe"],
         # build configurations
-        archs = ["x86_64"], #  limit to 64-bit only
+        archs=["x86_64"],  #  limit to 64-bit only
     )
     builder.add_common_builds(pure_c=True)
     for settings, options, env_vars, build_requires, reference in builder.items:
diff --git a/conanfile.py b/conanfile.py
index 76021ceb..1f5d68de 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -24,7 +24,10 @@ from conan import ConanFile
 from conan.tools.cmake import CMakeToolchain, CMakeDeps, CMake
 from conan.tools.files import copy, load, rmdir
 from conan.tools.scm import Version
-from conans.tools import get_env, check_min_cppstd   # TODO replace with new tools for Conan 2.0
+from conans.tools import (
+    get_env,
+    check_min_cppstd,
+)  # TODO replace with new tools for Conan 2.0
 import os, re
 
 required_conan_version = ">=1.48.0"
@@ -50,19 +53,18 @@ class MPUnitsConan(ConanFile):
     license = "MIT"
     url = "https://github.com/mpusz/units"
     settings = "os", "compiler", "build_type", "arch"
-    requires = (
-        "gsl-lite/0.40.0"
-    )
-    options = {
-        "downcast_mode": ["off", "on", "auto"],
-        "build_docs": [True, False]
-    }
-    default_options = {
-        "downcast_mode": "on",
-        "build_docs": True
-    }
+    requires = "gsl-lite/0.40.0"
+    options = {"downcast_mode": ["off", "on", "auto"], "build_docs": [True, False]}
+    default_options = {"downcast_mode": "on", "build_docs": True}
     exports = ["LICENSE.md"]
-    exports_sources = ["docs/*", "src/*", "test/*", "cmake/*", "example/*", "CMakeLists.txt"]
+    exports_sources = [
+        "docs/*",
+        "src/*",
+        "test/*",
+        "cmake/*",
+        "example/*",
+        "CMakeLists.txt",
+    ]
     no_copy_source = True
     generators = "cmake_paths"
 
@@ -74,9 +76,9 @@ class MPUnitsConan(ConanFile):
     def _use_libfmt(self):
         compiler = self.settings.compiler
         version = Version(self.settings.compiler.version)
-        std_support = \
-            (compiler == "Visual Studio" and version >= 17 and compiler.cppstd == 23) or \
-            (compiler == "msvc" and version >= 193 and compiler.cppstd == 23)
+        std_support = (
+            compiler == "Visual Studio" and version >= 17 and compiler.cppstd == 23
+        ) or (compiler == "msvc" and version >= 193 and compiler.cppstd == 23)
         return not std_support
 
     @property
@@ -95,7 +97,9 @@ class MPUnitsConan(ConanFile):
 
     def set_version(self):
         content = load(self, os.path.join(self.recipe_folder, "src/CMakeLists.txt"))
-        version = re.search(r"project\([^\)]+VERSION (\d+\.\d+\.\d+)[^\)]*\)", content).group(1)
+        version = re.search(
+            r"project\([^\)]+VERSION (\d+\.\d+\.\d+)[^\)]*\)", content
+        ).group(1)
         self.version = version.strip()
 
     def requirements(self):
@@ -124,10 +128,14 @@ class MPUnitsConan(ConanFile):
                 raise ConanInvalidConfiguration("mp-units requires at least clang++-12")
         elif compiler == "apple-clang":
             if version < 13:
-                raise ConanInvalidConfiguration("mp-units requires at least AppleClang 13")
+                raise ConanInvalidConfiguration(
+                    "mp-units requires at least AppleClang 13"
+                )
         elif compiler == "Visual Studio":
             if version < 16:
-                raise ConanInvalidConfiguration("mp-units requires at least Visual Studio 16.9")
+                raise ConanInvalidConfiguration(
+                    "mp-units requires at least Visual Studio 16.9"
+                )
         elif compiler == "msvc":
             if self._msvc_version < 1928:
                 raise ConanInvalidConfiguration("mp-units requires at least MSVC 19.28")
@@ -162,7 +170,12 @@ class MPUnitsConan(ConanFile):
         self.info.header_only()
 
     def package(self):
-        copy(self, "LICENSE.md", self.source_folder, os.path.join(self.package_folder, "licenses"))
+        copy(
+            self,
+            "LICENSE.md",
+            self.source_folder,
+            os.path.join(self.package_folder, "licenses"),
+        )
         cmake = CMake(self)
         cmake.install()
         rmdir(self, os.path.join(self.package_folder, "lib", "cmake"))
diff --git a/docs/conf.py b/docs/conf.py
index 382ae080..1dbe5187 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -12,152 +12,311 @@
 import re
 import sphinx_rtd_theme
 
-from pygments.lexer import RegexLexer, include, bygroups, using, \
-    this, inherit, default, words
+from pygments.lexer import (
+    RegexLexer,
+    include,
+    bygroups,
+    using,
+    this,
+    inherit,
+    default,
+    words,
+)
 from pygments.util import get_bool_opt
-from pygments.token import Text, Comment, Operator, Keyword, Name, String, \
-    Number, Punctuation, Error
+from pygments.token import (
+    Text,
+    Comment,
+    Operator,
+    Keyword,
+    Name,
+    String,
+    Number,
+    Punctuation,
+    Error,
+)
 from sphinx.highlighting import lexers
 
+
 class MyCFamilyLexer(RegexLexer):
     #: optional Comment or Whitespace
-    _ws = r'(?:\s|//.*?\n|/[*].*?[*]/)+'
+    _ws = r"(?:\s|//.*?\n|/[*].*?[*]/)+"
 
     # The trailing ?, rather than *, avoids a geometric performance drop here.
     #: only one /* */ style comment
-    _ws1 = r'\s*(?:/[*].*?[*]/\s*)?'
+    _ws1 = r"\s*(?:/[*].*?[*]/\s*)?"
 
     tokens = {
-        'whitespace': [
+        "whitespace": [
             # preprocessor directives: without whitespace
-            (r'^#if\s+0', Comment.Preproc, 'if0'),
-            ('^#', Comment.Preproc, 'macro'),
+            (r"^#if\s+0", Comment.Preproc, "if0"),
+            ("^#", Comment.Preproc, "macro"),
             # or with whitespace
-            ('^(' + _ws1 + r')(#if\s+0)',
-             bygroups(using(this), Comment.Preproc), 'if0'),
-            ('^(' + _ws1 + ')(#)',
-             bygroups(using(this), Comment.Preproc), 'macro'),
-            (r'\n', Text),
-            (r'\s+', Text),
-            (r'\\\n', Text),  # line continuation
-            (r'//(\n|[\w\W]*?[^\\]\n)', Comment.Single),
-            (r'/(\\\n)?[*][\w\W]*?[*](\\\n)?/', Comment.Multiline),
+            (
+                "^(" + _ws1 + r")(#if\s+0)",
+                bygroups(using(this), Comment.Preproc),
+                "if0",
+            ),
+            ("^(" + _ws1 + ")(#)", bygroups(using(this), Comment.Preproc), "macro"),
+            (r"\n", Text),
+            (r"\s+", Text),
+            (r"\\\n", Text),  # line continuation
+            (r"//(\n|[\w\W]*?[^\\]\n)", Comment.Single),
+            (r"/(\\\n)?[*][\w\W]*?[*](\\\n)?/", Comment.Multiline),
             # Open until EOF, so no ending delimeter
-            (r'/(\\\n)?[*][\w\W]*', Comment.Multiline),
+            (r"/(\\\n)?[*][\w\W]*", Comment.Multiline),
         ],
-        'statements': [
-            (r'(L?)(")', bygroups(String.Affix, String), 'string'),
-            (r"(L?)(')(\\.|\\[0-7]{1,3}|\\x[a-fA-F0-9]{1,2}|[^\\\'\n])(')",
-             bygroups(String.Affix, String.Char, String.Char, String.Char)),
-            (r'\*/', Error),
-            (r'[~!%^&*+=|?:<>/-]', Operator),
-            (r'[()\[\],.]', Punctuation),
-            (words(('asm', 'auto', 'break', 'case', 'const', 'continue',
-                    'default', 'do', 'else', 'enum', 'extern', 'for', 'goto',
-                    'if', 'register', 'restricted', 'return', 'sizeof',
-                    'static', 'struct', 'switch', 'typedef', 'union',
-                    'volatile', 'while'),
-                   suffix=r'\b'), Keyword),
-            (r'(bool|int|long|float|short|double|char|unsigned|signed|void)\b',
-             Keyword.Type),
-            (words(('inline', '_inline', '__inline', 'naked', 'restrict',
-                    'thread', 'typename'), suffix=r'\b'), Keyword.Reserved),
+        "statements": [
+            (r'(L?)(")', bygroups(String.Affix, String), "string"),
+            (
+                r"(L?)(')(\\.|\\[0-7]{1,3}|\\x[a-fA-F0-9]{1,2}|[^\\\'\n])(')",
+                bygroups(String.Affix, String.Char, String.Char, String.Char),
+            ),
+            (r"\*/", Error),
+            (r"[~!%^&*+=|?:<>/-]", Operator),
+            (r"[()\[\],.]", Punctuation),
+            (
+                words(
+                    (
+                        "asm",
+                        "auto",
+                        "break",
+                        "case",
+                        "const",
+                        "continue",
+                        "default",
+                        "do",
+                        "else",
+                        "enum",
+                        "extern",
+                        "for",
+                        "goto",
+                        "if",
+                        "register",
+                        "restricted",
+                        "return",
+                        "sizeof",
+                        "static",
+                        "struct",
+                        "switch",
+                        "typedef",
+                        "union",
+                        "volatile",
+                        "while",
+                    ),
+                    suffix=r"\b",
+                ),
+                Keyword,
+            ),
+            (
+                r"(bool|int|long|float|short|double|char|unsigned|signed|void)\b",
+                Keyword.Type,
+            ),
+            (
+                words(
+                    (
+                        "inline",
+                        "_inline",
+                        "__inline",
+                        "naked",
+                        "restrict",
+                        "thread",
+                        "typename",
+                    ),
+                    suffix=r"\b",
+                ),
+                Keyword.Reserved,
+            ),
             # Vector intrinsics
-            (r'(__m(128i|128d|128|64))\b', Keyword.Reserved),
+            (r"(__m(128i|128d|128|64))\b", Keyword.Reserved),
             # Microsoft-isms
-            (words((
-                'asm', 'int8', 'based', 'except', 'int16', 'stdcall', 'cdecl',
-                'fastcall', 'int32', 'declspec', 'finally', 'int64', 'try',
-                'leave', 'wchar_t', 'w64', 'unaligned', 'raise', 'noop',
-                'identifier', 'forceinline', 'assume'),
-                prefix=r'__', suffix=r'\b'), Keyword.Reserved),
-            (r'(true|false|NULL)\b', Name.Builtin),
-            (r'([a-zA-Z_]\w*)(\s*)(:)(?!:)', bygroups(Name.Label, Text, Punctuation)),
-            (r'[a-zA-Z_]\w*', Name),
+            (
+                words(
+                    (
+                        "asm",
+                        "int8",
+                        "based",
+                        "except",
+                        "int16",
+                        "stdcall",
+                        "cdecl",
+                        "fastcall",
+                        "int32",
+                        "declspec",
+                        "finally",
+                        "int64",
+                        "try",
+                        "leave",
+                        "wchar_t",
+                        "w64",
+                        "unaligned",
+                        "raise",
+                        "noop",
+                        "identifier",
+                        "forceinline",
+                        "assume",
+                    ),
+                    prefix=r"__",
+                    suffix=r"\b",
+                ),
+                Keyword.Reserved,
+            ),
+            (r"(true|false|NULL)\b", Name.Builtin),
+            (r"([a-zA-Z_]\w*)(\s*)(:)(?!:)", bygroups(Name.Label, Text, Punctuation)),
+            (r"[a-zA-Z_]\w*", Name),
         ],
-        'root': [
-            include('whitespace'),
+        "root": [
+            include("whitespace"),
             # functions
-            (r'((?:[\w*\s])+?(?:\s|[*]))'  # return arguments
-             r'([a-zA-Z_]\w*)'             # method name
-             r'(\s*\([^;]*?\))'            # signature
-             r'([^;{]*)(\{)',
-             bygroups(using(this), Name.Function, using(this), using(this),
-                      Punctuation),
-             'function'),
+            (
+                r"((?:[\w*\s])+?(?:\s|[*]))"  # return arguments
+                r"([a-zA-Z_]\w*)"  # method name
+                r"(\s*\([^;]*?\))"  # signature
+                r"([^;{]*)(\{)",
+                bygroups(
+                    using(this), Name.Function, using(this), using(this), Punctuation
+                ),
+                "function",
+            ),
             # function declarations
-            (r'((?:[\w*\s])+?(?:\s|[*]))'  # return arguments
-             r'([a-zA-Z_]\w*)'             # method name
-             r'(\s*\([^;]*?\))'            # signature
-             r'([^;]*)(;)',
-             bygroups(using(this), Name.Function, using(this), using(this),
-                      Punctuation)),
-            default('statement'),
+            (
+                r"((?:[\w*\s])+?(?:\s|[*]))"  # return arguments
+                r"([a-zA-Z_]\w*)"  # method name
+                r"(\s*\([^;]*?\))"  # signature
+                r"([^;]*)(;)",
+                bygroups(
+                    using(this), Name.Function, using(this), using(this), Punctuation
+                ),
+            ),
+            default("statement"),
         ],
-        'statement': [
-            include('whitespace'),
-            include('statements'),
-            ('[{}]', Punctuation),
-            (';', Punctuation, '#pop'),
+        "statement": [
+            include("whitespace"),
+            include("statements"),
+            ("[{}]", Punctuation),
+            (";", Punctuation, "#pop"),
         ],
-        'function': [
-            include('whitespace'),
-            include('statements'),
-            (';', Punctuation),
-            (r'\{', Punctuation, '#push'),
-            (r'\}', Punctuation, '#pop'),
+        "function": [
+            include("whitespace"),
+            include("statements"),
+            (";", Punctuation),
+            (r"\{", Punctuation, "#push"),
+            (r"\}", Punctuation, "#pop"),
         ],
-        'string': [
-            (r'"', String, '#pop'),
-            (r'\\([\\abfnrtv"\']|x[a-fA-F0-9]{2,4}|'
-             r'u[a-fA-F0-9]{4}|U[a-fA-F0-9]{8}|[0-7]{1,3})', String.Escape),
+        "string": [
+            (r'"', String, "#pop"),
+            (
+                r'\\([\\abfnrtv"\']|x[a-fA-F0-9]{2,4}|'
+                r"u[a-fA-F0-9]{4}|U[a-fA-F0-9]{8}|[0-7]{1,3})",
+                String.Escape,
+            ),
             (r'[^\\"\n]+', String),  # all other characters
-            (r'\\\n', String),  # line continuation
-            (r'\\', String),  # stray backslash
+            (r"\\\n", String),  # line continuation
+            (r"\\", String),  # stray backslash
         ],
-        'macro': [
-            (r'(include)(' + _ws1 + r')([^\n]+)',
-             bygroups(Comment.Preproc, Text, Comment.PreprocFile)),
-            (r'[^/\n]+', Comment.Preproc),
-            (r'/[*](.|\n)*?[*]/', Comment.Multiline),
-            (r'//.*?\n', Comment.Single, '#pop'),
-            (r'/', Comment.Preproc),
-            (r'(?<=\\)\n', Comment.Preproc),
-            (r'\n', Comment.Preproc, '#pop'),
+        "macro": [
+            (
+                r"(include)(" + _ws1 + r")([^\n]+)",
+                bygroups(Comment.Preproc, Text, Comment.PreprocFile),
+            ),
+            (r"[^/\n]+", Comment.Preproc),
+            (r"/[*](.|\n)*?[*]/", Comment.Multiline),
+            (r"//.*?\n", Comment.Single, "#pop"),
+            (r"/", Comment.Preproc),
+            (r"(?<=\\)\n", Comment.Preproc),
+            (r"\n", Comment.Preproc, "#pop"),
+        ],
+        "if0": [
+            (r"^\s*#if.*?(?<!\\)\n", Comment.Preproc, "#push"),
+            (r"^\s*#el(?:se|if).*\n", Comment.Preproc, "#pop"),
+            (r"^\s*#endif.*?(?<!\\)\n", Comment.Preproc, "#pop"),
+            (r".*?\n", Comment),
         ],
-        'if0': [
-            (r'^\s*#if.*?(?<!\\)\n', Comment.Preproc, '#push'),
-            (r'^\s*#el(?:se|if).*\n', Comment.Preproc, '#pop'),
-            (r'^\s*#endif.*?(?<!\\)\n', Comment.Preproc, '#pop'),
-            (r'.*?\n', Comment),
-        ]
     }
 
     stdlib_types = {
-        'size_t', 'ssize_t', 'off_t', 'wchar_t', 'ptrdiff_t', 'sig_atomic_t', 'fpos_t',
-        'clock_t', 'time_t', 'va_list', 'jmp_buf', 'FILE', 'DIR', 'div_t', 'ldiv_t',
-        'mbstate_t', 'wctrans_t', 'wint_t', 'wctype_t'}
+        "size_t",
+        "ssize_t",
+        "off_t",
+        "wchar_t",
+        "ptrdiff_t",
+        "sig_atomic_t",
+        "fpos_t",
+        "clock_t",
+        "time_t",
+        "va_list",
+        "jmp_buf",
+        "FILE",
+        "DIR",
+        "div_t",
+        "ldiv_t",
+        "mbstate_t",
+        "wctrans_t",
+        "wint_t",
+        "wctype_t",
+    }
     c99_types = {
-        '_Bool', '_Complex', 'int8_t', 'int16_t', 'int32_t', 'int64_t', 'uint8_t',
-        'uint16_t', 'uint32_t', 'uint64_t', 'int_least8_t', 'int_least16_t',
-        'int_least32_t', 'int_least64_t', 'uint_least8_t', 'uint_least16_t',
-        'uint_least32_t', 'uint_least64_t', 'int_fast8_t', 'int_fast16_t', 'int_fast32_t',
-        'int_fast64_t', 'uint_fast8_t', 'uint_fast16_t', 'uint_fast32_t', 'uint_fast64_t',
-        'intptr_t', 'uintptr_t', 'intmax_t', 'uintmax_t'}
+        "_Bool",
+        "_Complex",
+        "int8_t",
+        "int16_t",
+        "int32_t",
+        "int64_t",
+        "uint8_t",
+        "uint16_t",
+        "uint32_t",
+        "uint64_t",
+        "int_least8_t",
+        "int_least16_t",
+        "int_least32_t",
+        "int_least64_t",
+        "uint_least8_t",
+        "uint_least16_t",
+        "uint_least32_t",
+        "uint_least64_t",
+        "int_fast8_t",
+        "int_fast16_t",
+        "int_fast32_t",
+        "int_fast64_t",
+        "uint_fast8_t",
+        "uint_fast16_t",
+        "uint_fast32_t",
+        "uint_fast64_t",
+        "intptr_t",
+        "uintptr_t",
+        "intmax_t",
+        "uintmax_t",
+    }
     linux_types = {
-        'clockid_t', 'cpu_set_t', 'cpumask_t', 'dev_t', 'gid_t', 'id_t', 'ino_t', 'key_t',
-        'mode_t', 'nfds_t', 'pid_t', 'rlim_t', 'sig_t', 'sighandler_t', 'siginfo_t',
-        'sigset_t', 'sigval_t', 'socklen_t', 'timer_t', 'uid_t'}
+        "clockid_t",
+        "cpu_set_t",
+        "cpumask_t",
+        "dev_t",
+        "gid_t",
+        "id_t",
+        "ino_t",
+        "key_t",
+        "mode_t",
+        "nfds_t",
+        "pid_t",
+        "rlim_t",
+        "sig_t",
+        "sighandler_t",
+        "siginfo_t",
+        "sigset_t",
+        "sigval_t",
+        "socklen_t",
+        "timer_t",
+        "uid_t",
+    }
 
     def __init__(self, **options):
-        self.stdlibhighlighting = get_bool_opt(options, 'stdlibhighlighting', True)
-        self.c99highlighting = get_bool_opt(options, 'c99highlighting', True)
-        self.platformhighlighting = get_bool_opt(options, 'platformhighlighting', True)
+        self.stdlibhighlighting = get_bool_opt(options, "stdlibhighlighting", True)
+        self.c99highlighting = get_bool_opt(options, "c99highlighting", True)
+        self.platformhighlighting = get_bool_opt(options, "platformhighlighting", True)
         RegexLexer.__init__(self, **options)
 
     def get_tokens_unprocessed(self, text):
-        for index, token, value in \
-                RegexLexer.get_tokens_unprocessed(self, text):
+        for index, token, value in RegexLexer.get_tokens_unprocessed(self, text):
             if token is Name:
                 if self.stdlibhighlighting and value in self.stdlib_types:
                     token = Keyword.Type
@@ -172,65 +331,147 @@ class MyCppLexer(MyCFamilyLexer):
     """
     For C++ source code with preprocessor directives.
     """
-    name = 'My C++'
-    aliases = ['cpp', 'c++']
-    filenames = ['*.cpp', '*.hpp', '*.c++', '*.h++',
-                 '*.cc', '*.hh', '*.cxx', '*.hxx',
-                 '*.C', '*.H', '*.cp', '*.CPP']
-    mimetypes = ['text/x-c++hdr', 'text/x-c++src']
+
+    name = "My C++"
+    aliases = ["cpp", "c++"]
+    filenames = [
+        "*.cpp",
+        "*.hpp",
+        "*.c++",
+        "*.h++",
+        "*.cc",
+        "*.hh",
+        "*.cxx",
+        "*.hxx",
+        "*.C",
+        "*.H",
+        "*.cp",
+        "*.CPP",
+    ]
+    mimetypes = ["text/x-c++hdr", "text/x-c++src"]
     priority = 0.1
 
     tokens = {
-        'statements': [
-            (words((
-                'catch', 'const_cast', 'delete', 'dynamic_cast', 'explicit',
-                'export', 'friend', 'mutable', 'namespace', 'new', 'operator',
-                'private', 'protected', 'public', 'reinterpret_cast',
-                'restrict', 'static_cast', 'template', 'this', 'throw', 'throws',
-                'try', 'typeid', 'typename', 'using', 'virtual',
-                'constexpr', 'nullptr', 'decltype', 'thread_local',
-                'alignas', 'alignof', 'static_assert', 'noexcept', 'override',
-                'final', 'constinit', 'consteval', 'constinit', 'concept', 'co_await',
-                'co_return', 'co_yield', 'requires', 'import', 'module'), suffix=r'\b'), Keyword),
-            (r'char(16_t|32_t|8_t)\b', Keyword.Type),
-            (r'(class)(\s+)', bygroups(Keyword, Text), 'classname'),
+        "statements": [
+            (
+                words(
+                    (
+                        "catch",
+                        "const_cast",
+                        "delete",
+                        "dynamic_cast",
+                        "explicit",
+                        "export",
+                        "friend",
+                        "mutable",
+                        "namespace",
+                        "new",
+                        "operator",
+                        "private",
+                        "protected",
+                        "public",
+                        "reinterpret_cast",
+                        "restrict",
+                        "static_cast",
+                        "template",
+                        "this",
+                        "throw",
+                        "throws",
+                        "try",
+                        "typeid",
+                        "typename",
+                        "using",
+                        "virtual",
+                        "constexpr",
+                        "nullptr",
+                        "decltype",
+                        "thread_local",
+                        "alignas",
+                        "alignof",
+                        "static_assert",
+                        "noexcept",
+                        "override",
+                        "final",
+                        "constinit",
+                        "consteval",
+                        "constinit",
+                        "concept",
+                        "co_await",
+                        "co_return",
+                        "co_yield",
+                        "requires",
+                        "import",
+                        "module",
+                    ),
+                    suffix=r"\b",
+                ),
+                Keyword,
+            ),
+            (r"char(16_t|32_t|8_t)\b", Keyword.Type),
+            (r"(class)(\s+)", bygroups(Keyword, Text), "classname"),
             # C++11 raw strings
-            (r'(R)(")([^\\()\s]{,16})(\()((?:.|\n)*?)(\)\3)(")',
-             bygroups(String.Affix, String, String.Delimiter, String.Delimiter,
-                      String, String.Delimiter, String)),
+            (
+                r'(R)(")([^\\()\s]{,16})(\()((?:.|\n)*?)(\)\3)(")',
+                bygroups(
+                    String.Affix,
+                    String,
+                    String.Delimiter,
+                    String.Delimiter,
+                    String,
+                    String.Delimiter,
+                    String,
+                ),
+            ),
             # C++11 UTF-8/16/32 strings
-            (r'(u8|u|U)(")', bygroups(String.Affix, String), 'string'),
+            (r'(u8|u|U)(")', bygroups(String.Affix, String), "string"),
             # C++14 number separators
-            (r'(\d[\d\']*\.[\d\']*|\.\d[\d\']*|\d[\d\']*)[eE][+-]?\d[\d\']*[LlUu]*', Number.Float),
-            (r'(\d[\d\']*\.[\d\']*|\.\d[\d\']*|\d[\d\']*[fF])[fF]?', Number.Float),
-            (r'0x[0-9a-fA-F\']+[LlUu]*', Number.Hex),
-            (r'0[0-7\']+[LlUu]*', Number.Oct),
-            (r'\d[\d\']*[LlUu]*', Number.Integer),
+            (
+                r"(\d[\d\']*\.[\d\']*|\.\d[\d\']*|\d[\d\']*)[eE][+-]?\d[\d\']*[LlUu]*",
+                Number.Float,
+            ),
+            (r"(\d[\d\']*\.[\d\']*|\.\d[\d\']*|\d[\d\']*[fF])[fF]?", Number.Float),
+            (r"0x[0-9a-fA-F\']+[LlUu]*", Number.Hex),
+            (r"0[0-7\']+[LlUu]*", Number.Oct),
+            (r"\d[\d\']*[LlUu]*", Number.Integer),
             inherit,
         ],
-        'root': [
+        "root": [
             inherit,
             # C++ Microsoft-isms
-            (words(('virtual_inheritance', 'uuidof', 'super', 'single_inheritance',
-                    'multiple_inheritance', 'interface', 'event'),
-                   prefix=r'__', suffix=r'\b'), Keyword.Reserved),
+            (
+                words(
+                    (
+                        "virtual_inheritance",
+                        "uuidof",
+                        "super",
+                        "single_inheritance",
+                        "multiple_inheritance",
+                        "interface",
+                        "event",
+                    ),
+                    prefix=r"__",
+                    suffix=r"\b",
+                ),
+                Keyword.Reserved,
+            ),
             # Offload C++ extensions, http://offload.codeplay.com/
-            (r'__(offload|blockingoffload|outer)\b', Keyword.Pseudo),
+            (r"__(offload|blockingoffload|outer)\b", Keyword.Pseudo),
         ],
-        'classname': [
-            (r'[a-zA-Z_]\w*', Name.Class, '#pop'),
+        "classname": [
+            (r"[a-zA-Z_]\w*", Name.Class, "#pop"),
             # template specification
-            (r'\s*(?=>)', Text, '#pop'),
+            (r"\s*(?=>)", Text, "#pop"),
         ],
     }
 
     def analyse_text(text):
-        if re.search('#include <[a-z_]+>', text):
+        if re.search("#include <[a-z_]+>", text):
             return 0.2
-        if re.search('using namespace ', text):
+        if re.search("using namespace ", text):
             return 0.4
 
-lexers['cpp'] = MyCppLexer(startinline=True)
+
+lexers["cpp"] = MyCppLexer(startinline=True)
 
 # TODO Remove the above when Pygments release with fixes is available
 
@@ -243,11 +484,14 @@ lexers['cpp'] = MyCppLexer(startinline=True)
 
 import subprocess, os, re
 
+
 def get_version():
     try:
-        with open('../src/CMakeLists.txt', 'r') as file:
+        with open("../src/CMakeLists.txt", "r") as file:
             content = file.read()
-        version = re.search(r"project\([^\)]+VERSION (\d+\.\d+\.\d+)[^\)]*\)", content).group(1)
+        version = re.search(
+            r"project\([^\)]+VERSION (\d+\.\d+\.\d+)[^\)]*\)", content
+        ).group(1)
         return version.strip()
     except Exception:
         return None
@@ -255,9 +499,9 @@ def get_version():
 
 # -- Project information -----------------------------------------------------
 
-project = 'mp-units'
-copyright = '2018-present, Mateusz Pusz'
-author = 'Mateusz Pusz'
+project = "mp-units"
+copyright = "2018-present, Mateusz Pusz"
+author = "Mateusz Pusz"
 
 # The major project version, used as the replacement for |version|.
 version = get_version()
@@ -270,21 +514,21 @@ release = get_version()
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
 extensions = [
-    'sphinx.ext.autosectionlabel',
-    'sphinx.ext.githubpages',
-    'sphinx.ext.graphviz',
-    'sphinx_rtd_theme',
-    'recommonmark',
-    'breathe'
+    "sphinx.ext.autosectionlabel",
+    "sphinx.ext.githubpages",
+    "sphinx.ext.graphviz",
+    "sphinx_rtd_theme",
+    "recommonmark",
+    "breathe",
 ]
 
 # Add any paths that contain templates here, relative to this directory.
-templates_path = ['_templates']
+templates_path = ["_templates"]
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.
 # This pattern also affects html_static_path and html_extra_path.
-exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']
+exclude_patterns = ["_build", "Thumbs.db", ".DS_Store"]
 
 # If true, Sphinx will warn about all references where the target cannot
 # be found. Default is False.
@@ -305,29 +549,29 @@ autosectionlabel_prefix_document = True
 
 # The name of the default domain. Can also be None to disable a default
 # domain. The default is 'py'.
-primary_domain = 'cpp'
+primary_domain = "cpp"
 
 # The reST default role (used for this markup: `text`) to use for all documents.
-default_role = 'cpp:any'
+default_role = "cpp:any"
 
 # The default language to highlight source code in. The default is 'python3'.
 # The value should be a valid Pygments lexer name (https://pygments.org/docs/lexers).
-highlight_language = 'cpp'
+highlight_language = "cpp"
 
 # The style name to use for Pygments highlighting of source code. If not set,
 # either the theme’s default style or 'sphinx' is selected for HTML output.
-pygments_style = 'default'
+pygments_style = "default"
 
 # A list of prefixes that will be ignored when sorting C++ objects in the global
 # index. For example ['awesome_lib::'].
-cpp_index_common_prefix = ['units::']
+cpp_index_common_prefix = ["units::"]
 
 
 # -- Options for HTML output -------------------------------------------------
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
-html_theme = 'sphinx_rtd_theme'
+html_theme = "sphinx_rtd_theme"
 
 # A dictionary of options that influence the look and feel of the selected theme.
 # These are theme-specific.
@@ -339,7 +583,7 @@ html_theme_options = {
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ['_static']
+html_static_path = ["_static"]
 
 # If given, this must be the name of an image file (path relative to the
 # configuration directory) that is the logo of the docs. It is placed at the
@@ -349,45 +593,45 @@ html_static_path = ['_static']
 
 # These paths are either relative to html_static_path or fully qualified
 # paths (eg. https://...)
-html_css_files = [
-    'css/custom.css'
-]
+html_css_files = ["css/custom.css"]
 
 
 # -- Breathe configuration ---------------------------------------------------
 
+
 def configureDoxyfile(input_dir, output_dir):
-    with open('Doxyfile.in', 'r') as file:
+    with open("Doxyfile.in", "r") as file:
         filedata = file.read()
 
-    filedata = filedata.replace('@DOXYGEN_INPUT_DIR@', input_dir)
-    filedata = filedata.replace('@DOXYGEN_OUTPUT_DIR@', output_dir)
+    filedata = filedata.replace("@DOXYGEN_INPUT_DIR@", input_dir)
+    filedata = filedata.replace("@DOXYGEN_OUTPUT_DIR@", output_dir)
 
-    with open('Doxyfile', 'w') as file:
+    with open("Doxyfile", "w") as file:
         file.write(filedata)
 
+
 # Check if we're running on Read the Docs' servers
-read_the_docs_build = os.environ.get('READTHEDOCS', None) == 'True'
+read_the_docs_build = os.environ.get("READTHEDOCS", None) == "True"
 
 # This should be a dictionary in which the keys are project names and the values
 # are paths to the folder containing the doxygen output for that project.
 breathe_projects = {}
 if read_the_docs_build:
-    input_dir = '../src'
-    output_dir = 'build'
+    input_dir = "../src"
+    output_dir = "build"
     configureDoxyfile(input_dir, output_dir)
-    subprocess.call('doxygen', shell=True)
-    breathe_projects['mp-units'] = output_dir + '/xml'
+    subprocess.call("doxygen", shell=True)
+    breathe_projects["mp-units"] = output_dir + "/xml"
 
 # This should match one of the keys in the breathe_projects dictionary and
 # indicates which project should be used when the project is not specified on
 # the directive.
-breathe_default_project = 'mp-units'
+breathe_default_project = "mp-units"
 
 # Allows you to specify domains for particular files according to their extension.
-breathe_domain_by_extension = {"h" : "cpp"}
+breathe_domain_by_extension = {"h": "cpp"}
 
 # Provides the directive flags that should be applied to all directives which
 # take :members:, :private-members: and :undoc-members: options. By default,
 # this is set to an empty list, which means no members are displayed.
-breathe_default_members = ('members', )
+breathe_default_members = ("members",)

From 23a62531bd6be16fbbbeb14d5e719a2d0ffd68b8 Mon Sep 17 00:00:00 2001
From: Markus Hofbauer <markus.hofbauer@tum.de>
Date: Thu, 12 May 2022 14:00:10 +0200
Subject: [PATCH 59/68] add python import sort

---
 .pre-commit-config.yaml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index dd44ca4c..81743f78 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -23,3 +23,8 @@ repos:
     hooks:
       - id: black
         language_version: python3
+  - repo: https://github.com/PyCQA/isort
+    rev: 5.10.1
+    hooks:
+      - id: isort
+        args: [--profile, black, --multi-line, "3"]

From 9365344a607579ee3aefe567e8af5a2c463785b5 Mon Sep 17 00:00:00 2001
From: Markus Hofbauer <markus.hofbauer@tum.de>
Date: Thu, 12 May 2022 14:00:18 +0200
Subject: [PATCH 60/68] apply python isort

---
 conanfile.py              | 12 +++++++-----
 docs/conf.py              | 24 +++++++++++++-----------
 test_package/conanfile.py |  2 +-
 3 files changed, 21 insertions(+), 17 deletions(-)

diff --git a/conanfile.py b/conanfile.py
index 1f5d68de..a2189cd9 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -20,15 +20,17 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+import os
+import re
+
 from conan import ConanFile
-from conan.tools.cmake import CMakeToolchain, CMakeDeps, CMake
+from conan.tools.cmake import CMake, CMakeDeps, CMakeToolchain
 from conan.tools.files import copy, load, rmdir
 from conan.tools.scm import Version
-from conans.tools import (
-    get_env,
+from conans.tools import (  # TODO replace with new tools for Conan 2.0
     check_min_cppstd,
-)  # TODO replace with new tools for Conan 2.0
-import os, re
+    get_env,
+)
 
 required_conan_version = ">=1.48.0"
 
diff --git a/docs/conf.py b/docs/conf.py
index 1dbe5187..9c997601 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -10,30 +10,30 @@
 """
 
 import re
-import sphinx_rtd_theme
 
+import sphinx_rtd_theme
 from pygments.lexer import (
     RegexLexer,
-    include,
     bygroups,
-    using,
-    this,
-    inherit,
     default,
+    include,
+    inherit,
+    this,
+    using,
     words,
 )
-from pygments.util import get_bool_opt
 from pygments.token import (
-    Text,
     Comment,
-    Operator,
+    Error,
     Keyword,
     Name,
-    String,
     Number,
+    Operator,
     Punctuation,
-    Error,
+    String,
+    Text,
 )
+from pygments.util import get_bool_opt
 from sphinx.highlighting import lexers
 
 
@@ -482,7 +482,9 @@ lexers["cpp"] = MyCppLexer(startinline=True)
 # For a full list see the documentation:
 # https://www.sphinx-doc.org/en/master/usage/configuration.html
 
-import subprocess, os, re
+import os
+import re
+import subprocess
 
 
 def get_version():
diff --git a/test_package/conanfile.py b/test_package/conanfile.py
index 9a98ad73..bad61ec8 100644
--- a/test_package/conanfile.py
+++ b/test_package/conanfile.py
@@ -20,8 +20,8 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-from conans import ConanFile, tools
 from conan.tools.cmake import CMake
+from conans import ConanFile, tools
 
 
 class TestPackageConan(ConanFile):

From 50a0e0dc814732a6197cf524dfaa9c194a854864 Mon Sep 17 00:00:00 2001
From: Markus Hofbauer <markus.hofbauer@tum.de>
Date: Thu, 12 May 2022 14:07:09 +0200
Subject: [PATCH 61/68] add flak8 check

---
 .flake8                 | 2 ++
 .pre-commit-config.yaml | 4 ++++
 2 files changed, 6 insertions(+)
 create mode 100644 .flake8

diff --git a/.flake8 b/.flake8
new file mode 100644
index 00000000..6deafc26
--- /dev/null
+++ b/.flake8
@@ -0,0 +1,2 @@
+[flake8]
+max-line-length = 120
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 81743f78..1a890db6 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -28,3 +28,7 @@ repos:
     hooks:
       - id: isort
         args: [--profile, black, --multi-line, "3"]
+  - repo: https://github.com/PyCQA/flake8
+    rev: 4.0.1
+    hooks:
+      - id: flake8

From 4b280d9e1fce2adce817fefe0fbe7960a2c867a8 Mon Sep 17 00:00:00 2001
From: Markus Hofbauer <markus.hofbauer@tum.de>
Date: Thu, 12 May 2022 14:07:49 +0200
Subject: [PATCH 62/68] fix flake8 warnings

---
 build.py     | 2 +-
 conanfile.py | 1 +
 docs/conf.py | 7 ++-----
 3 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/build.py b/build.py
index c397b944..e3bc1a56 100644
--- a/build.py
+++ b/build.py
@@ -38,7 +38,7 @@ if __name__ == "__main__":
         upload_dependencies="all",
         pip_install=["sphinx", "recommonmark", "breathe"],
         # build configurations
-        archs=["x86_64"],  #  limit to 64-bit only
+        archs=["x86_64"],  # limit to 64-bit only
     )
     builder.add_common_builds(pure_c=True)
     for settings, options, env_vars, build_requires, reference in builder.items:
diff --git a/conanfile.py b/conanfile.py
index a2189cd9..0c821dcd 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -27,6 +27,7 @@ from conan import ConanFile
 from conan.tools.cmake import CMake, CMakeDeps, CMakeToolchain
 from conan.tools.files import copy, load, rmdir
 from conan.tools.scm import Version
+from conans.errors import ConanInvalidConfiguration
 from conans.tools import (  # TODO replace with new tools for Conan 2.0
     check_min_cppstd,
     get_env,
diff --git a/docs/conf.py b/docs/conf.py
index 9c997601..54aa719b 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -9,9 +9,10 @@
     :license: BSD, see LICENSE for details.
 """
 
+import os
 import re
+import subprocess
 
-import sphinx_rtd_theme
 from pygments.lexer import (
     RegexLexer,
     bygroups,
@@ -482,10 +483,6 @@ lexers["cpp"] = MyCppLexer(startinline=True)
 # For a full list see the documentation:
 # https://www.sphinx-doc.org/en/master/usage/configuration.html
 
-import os
-import re
-import subprocess
-
 
 def get_version():
     try:

From 84c073fd36b4820d23811b6868e83f856f71d1a9 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 12 May 2022 17:09:38 +0200
Subject: [PATCH 63/68] build: doxygen updated to 1.9.4

---
 conanfile.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/conanfile.py b/conanfile.py
index 0c821dcd..50ea39bb 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -117,7 +117,7 @@ class MPUnitsConan(ConanFile):
             self.test_requires("catch2/2.13.9")
             self.test_requires("wg21-linear_algebra/0.7.2")
             if self.options.build_docs:
-                self.tool_requires("doxygen/1.9.2")
+                self.tool_requires("doxygen/1.9.4")
 
     # TODO Replace with `valdate()` for Conan 2.0 (https://github.com/conan-io/conan/issues/10723)
     def configure(self):

From 33f837a2f1588fc94edb9afe9c97fea5c5298d34 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 12 May 2022 17:10:11 +0200
Subject: [PATCH 64/68] build: `conanfile.py` formatting fixed

---
 conanfile.py | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/conanfile.py b/conanfile.py
index 50ea39bb..a673412e 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -28,10 +28,9 @@ from conan.tools.cmake import CMake, CMakeDeps, CMakeToolchain
 from conan.tools.files import copy, load, rmdir
 from conan.tools.scm import Version
 from conans.errors import ConanInvalidConfiguration
-from conans.tools import (  # TODO replace with new tools for Conan 2.0
-    check_min_cppstd,
-    get_env,
-)
+
+# TODO replace with new tools for Conan 2.0
+from conans.tools import check_min_cppstd, get_env
 
 required_conan_version = ">=1.48.0"
 

From a34ccb15aec433fc27e05a4c933af260d99ee406 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 12 May 2022 17:11:22 +0200
Subject: [PATCH 65/68] chore(gitpod): clang-14 enabled on Gitpod

---
 .gitpod.Dockerfile |  2 ++
 .gitpod.yml        | 20 +++++++++++++++++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/.gitpod.Dockerfile b/.gitpod.Dockerfile
index d944277b..49164bc2 100644
--- a/.gitpod.Dockerfile
+++ b/.gitpod.Dockerfile
@@ -3,10 +3,12 @@ FROM trainiteu/gitpod-cpp
 # Add clang-12 and clang-15 apt repositories
 RUN lsb_rel=`lsb_release -cs` \
   && sudo add-apt-repository "deb http://apt.llvm.org/${lsb_rel}/ llvm-toolchain-${lsb_rel}-12 main" \
+  && sudo add-apt-repository "deb http://apt.llvm.org/${lsb_rel}/ llvm-toolchain-${lsb_rel}-13 main" \
   && sudo add-apt-repository "deb http://apt.llvm.org/${lsb_rel}/ llvm-toolchain-${lsb_rel} main"
 
 # Install older compilers supported by the project as well as clang-format-15 for code formatting
 RUN sudo install-packages \
   g++-10 \
   clang-12 \
+  clang-13 \
   clang-format-15
diff --git a/.gitpod.yml b/.gitpod.yml
index 68f2d92e..fe00fec5 100644
--- a/.gitpod.yml
+++ b/.gitpod.yml
@@ -84,6 +84,7 @@ tasks:
       cp default gcc11
       cp default clang12
       cp default clang13
+      cp default clang14
       popd
       conan profile update settings.compiler.version=10 gcc10
       conan profile update env.CXX=/usr/bin/g++-10 gcc10
@@ -95,9 +96,14 @@ tasks:
       conan profile update env.CC=/usr/bin/clang-12 clang12
       conan profile update settings.compiler=clang clang13
       conan profile update settings.compiler.version=13 clang13
-      conan profile update settings.compiler.libcxx=libc++ clang13
+      conan profile update settings.compiler.libcxx=libstdc++11 clang13
       conan profile update env.CXX=/usr/bin/clang++-13 clang13
       conan profile update env.CC=/usr/bin/clang-13 clang13
+      conan profile update settings.compiler=clang clang14
+      conan profile update settings.compiler.version=14 clang14
+      conan profile update settings.compiler.libcxx=libc++ clang14
+      conan profile update env.CXX=/usr/bin/clang++-14 clang14
+      conan profile update env.CC=/usr/bin/clang-14 clang14
       gp sync-done conan-init
       exit
   - name: gcc-10
@@ -149,6 +155,18 @@ tasks:
       ctest -C Release
       ctest -C Debug
       echo "🛠️ clang-13 pre-build done! You can close this terminal and use 'Build' button in the VSCode status bar for incremental builds. 🛠️"
+  - name: clang-14
+    init: |
+      gp sync-await conan-init
+      mkdir -p build/Clang-14 && cd build/Clang-14
+      conan install ../.. -pr clang4 -e mp-units:CONAN_RUN_TESTS=True -o build_docs=False -b outdated
+      conan install ../.. -pr clang14 -e mp-units:CONAN_RUN_TESTS=True -o build_docs=False -b outdated -s build_type=Debug
+      cmake ../.. --no-warn-unused-cli --toolchain conan_toolchain.cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=TRUE -DCMAKE_C_COMPILER=/usr/bin/clang-14 -DCMAKE_CXX_COMPILER=/usr/bin/clang++-14
+      cmake --build . --config Release -j
+      cmake --build . --config Debug -j
+      ctest -C Release
+      ctest -C Debug
+      echo "🛠️ clang-14 pre-build done! You can close this terminal and use 'Build' button in the VSCode status bar for incremental builds. 🛠️"
   - name: documentation
     init: |
       gp sync-await conan-init

From 1f6f5817ae562aebc37ad6bd68ee8b616859a53a Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 12 May 2022 17:12:00 +0200
Subject: [PATCH 66/68] docs: `CHANGELOG.md` updated

---
 docs/CHANGELOG.md | 54 +++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 48 insertions(+), 6 deletions(-)

diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 2982bbea..fc803b52 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -2,18 +2,60 @@
 
 - **0.8.0 WIP**
   - (!) refactor: `common_quantity`, `common_quantity_for`, `common_quantity_point`, `common_quantity_kind`, and `common_quantity_point_kind` removed
+  - (!) refactor: `named_derived_unit` removed as it was not used
+  - (!) refactor: `derived_unit` renamed to `derived_scaled_unit`
+  - (!) refactor: `unit` renamed to `derived_unit`
+  - (!) refactor: `U::is_named` removed from the unit types and replaced with `NamedUnit` concept
+  - (!) refactor: `PrefixFamily` support removed
+  - (!) refactor: `mi(naut)` renamed to `nmi`
+  - (!) refactor: `knot` unit helper renamed to `kn` in FPS
+  - (!) refactor: `knot` text symbol changed from `"knot"` to `"kn`"
   - refactor: `quantity` `op+()` and `op-()` reimplemented in terms of `reference` rather then `quantity` types
-  - feat: `std::format` support for compliant compilers added
+  - refactor(example): `glide_computer` now use dimensionless quantities with `ranged_representation` as `rep`
   - feat: HEP system support added (thanks [@RalphSteinhagen](https://github.com/RalphSteinhagen))
+  - feat: `floor()`, `ceil()`, and `round()` support added (thanks [@hofbi](https://github.com/hofbi))
+  - feat: `std::format` support for compliant compilers added
   - feat: conversion helpers from `mp-units` to `std::chrono` types added
+  - feat: math functions can now be safely used with user-defined types
+  - feat: conversion from `quantity_point` to `std::chrono::time_point` added
+  - feat: `nautical_mile_per_hour` and `knot` added to `si::international` system
   - (!) fix: add `quantity_point::origin`, like `std::chrono::time_point::clock`
+  - fix: enable any prefixes for most of the named units (beside those that use prefixes already)
+  - fix: `hectare` definition fixed to be a prefixed version of `are` + other units
   - fix: account for different dimensions in `quantity_point_cast`'s constraint
-  - build: Minimum Conan version changed to 1.40
+  - fix: output stream operator now properly handles state
+  - fix: `fmt` algorithms were overconstrained with `forward_iterator`
+  - fix: CTAD for aliases fixed
+  - fix: `derived_ratio` calculation
+  - fix: `fill_t` assignment operator fixed
+  - fix: improve downcast mode off
+  - fix: `radioactivity` header compilation fixed
+  - fix: `si::hep::dim_momentum` duplicated definition fixed
+  - fix: `fps` can now coexist with `international` system
+  - fix: public headers fixed to be standalone
+  - test: standalone public headers tests added
+  - (!) build: CMake generator in Conan is no longer obtained from an environment variable
+  - (!) build: Required Conan version bumped to 1.48
+  - (!) build: Conan 1.48 does not set `CMAKE_BUILD_TYPE` in the `conan_toolchain.cmake` anymore
+  - build: AppleClang 13 support added (thanks [@fdischner](https://github.com/fdischner))
+  - build: most of the `conanfile.py` refactored to be Conan 2.0 ready
+  - build: `validate()` replaced with `configure()` to raise errors during `conan install` in Conan 1.X
+  - build: minimum Conan version changed to 1.40
+  - build: `linear-algebra` Conan repo is no needed anymore
+  - build: Gitpod support added
+  - build: clang-format-15 support added
+  - build: export config to local build (#322)
+  - build: fix export name of `mp-units-system`
   - build: fmt updated to 8.0.1
-  - build: gsl-lite updated to 0.38.1
-  - build: catch2 updated to 2.13.7
-  - build: doxygen updated to 1.9.2
-  - build: linear algebra switched to wg21-linear_algebra/0.7.2
+  - build: gsl-lite updated to 0.40.0
+  - build: catch2 updated to 2.13.9
+  - build: doxygen updated to 1.9.4
+  - build: linear_algebra/0.7.0 switched to wg21-linear_algebra/0.7.2
+  - ci: VS2022, gcc-11, clang-13, clang-14, and AppleClang 13 support added
+  - ci: pre-commit support added (thanks [@hofbi](https://github.com/hofbi))
+  - docs: Project documentation updated
+  - docs: `CITATION.cff` file added
+  - docs: `CONTRIBUTING.md` updated
 
 - **0.7.0 May 11, 2021**
   - (!) refactor: `ScalableNumber` renamed to `Representation`

From 8c0f9d4f8ef712633d4709bac1cbd00b71b50570 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 12 May 2022 17:12:35 +0200
Subject: [PATCH 67/68] build: `test_package/conanfile.py` updated for Conan
 2.0

---
 test_package/conanfile.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test_package/conanfile.py b/test_package/conanfile.py
index bad61ec8..1afb178a 100644
--- a/test_package/conanfile.py
+++ b/test_package/conanfile.py
@@ -20,8 +20,9 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+from conan import ConanFile
 from conan.tools.cmake import CMake
-from conans import ConanFile, tools
+from conan.tools.build import cross_building
 
 
 class TestPackageConan(ConanFile):
@@ -38,5 +39,5 @@ class TestPackageConan(ConanFile):
         cmake.build()
 
     def test(self):
-        if not tools.cross_building(self.settings):
+        if not cross_building(self):
             self.run("test_package", run_environment=True)

From 59fa420272ce2772b804dee56dfd5c5bc363097e Mon Sep 17 00:00:00 2001
From: Chip Hogg <chogg@aurora.tech>
Date: Thu, 12 May 2022 16:52:05 +0000
Subject: [PATCH 68/68] Fix remaining builds/tests

---
 src/core/include/units/unit.h                      | 14 +++++++-------
 .../si-fps/include/units/isq/si/fps/length.h       |  3 +--
 test/unit_test/runtime/fmt_units_test.cpp          |  2 +-
 3 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/src/core/include/units/unit.h b/src/core/include/units/unit.h
index f5d14220..c429f837 100644
--- a/src/core/include/units/unit.h
+++ b/src/core/include/units/unit.h
@@ -126,7 +126,7 @@ struct prefixed_unit : downcast_dispatch<Child, scaled_unit<P::mag * U::mag, typ
  * @tparam Child inherited class type used by the downcasting facility (CRTP Idiom)
  */
 template<typename Child>
-struct derived_unit : downcast_dispatch<Child, scaled_unit<ratio(1), Child>> {};
+struct derived_unit : downcast_dispatch<Child, scaled_unit<as_magnitude<1>(), Child>> {};
 
 /**
  * @brief A unit with a deduced ratio and symbol
@@ -195,8 +195,8 @@ namespace detail {
 template<typename Child, basic_symbol_text Symbol>
 void is_named_impl(const volatile named_unit<Child, Symbol>*);
 
-template<typename Child, basic_symbol_text Symbol, ratio R, typename U>
-void is_named_impl(const volatile named_scaled_unit<Child, Symbol, R, U>*);
+template<typename Child, basic_symbol_text Symbol, Magnitude auto M, typename U>
+void is_named_impl(const volatile named_scaled_unit<Child, Symbol, M, U>*);
 
 template<typename Child, typename P, typename U>
 void is_named_impl(const volatile prefixed_unit<Child, P, U>*);
@@ -213,8 +213,8 @@ inline constexpr bool is_named<U> = requires(U * u) { is_named_impl(u); };
 template<typename Child, basic_symbol_text Symbol>
 void can_be_prefixed_impl(const volatile named_unit<Child, Symbol>*);
 
-template<typename Child, basic_symbol_text Symbol, ratio R, typename U>
-void can_be_prefixed_impl(const volatile named_scaled_unit<Child, Symbol, R, U>*);
+template<typename Child, basic_symbol_text Symbol, Magnitude auto M, typename U>
+void can_be_prefixed_impl(const volatile named_scaled_unit<Child, Symbol, M, U>*);
 
 template<typename U, basic_symbol_text Symbol>
 void can_be_prefixed_impl(const volatile alias_unit<U, Symbol>*);
@@ -222,8 +222,8 @@ void can_be_prefixed_impl(const volatile alias_unit<U, Symbol>*);
 template<Unit U>
 inline constexpr bool can_be_prefixed<U> = requires(U * u) { can_be_prefixed_impl(u); };
 
-template<ratio R, typename U>
-inline constexpr bool can_be_prefixed<scaled_unit<R, U>> = can_be_prefixed<typename U::reference>;
+template<Magnitude auto M, typename U>
+inline constexpr bool can_be_prefixed<scaled_unit<M, U>> = can_be_prefixed<typename U::reference>;
 
 }  // namespace detail
 
diff --git a/src/systems/si-fps/include/units/isq/si/fps/length.h b/src/systems/si-fps/include/units/isq/si/fps/length.h
index 35f51d7f..04a9e930 100644
--- a/src/systems/si-fps/include/units/isq/si/fps/length.h
+++ b/src/systems/si-fps/include/units/isq/si/fps/length.h
@@ -39,6 +39,7 @@ using si::international::fathom;
 using si::international::foot;
 using si::international::inch;
 using si::international::mil;
+using si::international::mile;
 using si::international::thou;
 using si::international::yard;
 
@@ -47,8 +48,6 @@ struct thousandth : alias_unit<thou, "thou"> {};
 
 struct kiloyard : prefixed_unit<kiloyard, si::kilo, yard> {};
 
-struct mile : named_scaled_unit<mile, "mile", as_magnitude<5'280>(), foot> {};
-
 struct nautical_mile : named_scaled_unit<nautical_mile, "nmi", as_magnitude<2'000>(), yard> {};
 
 struct dim_length : isq::dim_length<foot> {};
diff --git a/test/unit_test/runtime/fmt_units_test.cpp b/test/unit_test/runtime/fmt_units_test.cpp
index 22c04fe2..58531174 100644
--- a/test/unit_test/runtime/fmt_units_test.cpp
+++ b/test/unit_test/runtime/fmt_units_test.cpp
@@ -66,7 +66,7 @@ TEST_CASE("std::format on synthesized unit symbols", "[text][fmt]")
     CHECK(STD_FMT::format("{}", 1_q_fathom_us) == "1 fathom(us)");
     CHECK(STD_FMT::format("{}", 1_q_mi) == "1 mi");
     CHECK(STD_FMT::format("{}", 1_q_mi_us) == "1 mi(us)");
-    CHECK(STD_FMT::format("{}", 1_q_naut_mi) == "1 nmi");
+    CHECK(STD_FMT::format("{}", 1_q_naut_mi) == "1 mi(naut)");
     CHECK(STD_FMT::format("{}", 1_q_ch) == "1 ch");
     CHECK(STD_FMT::format("{}", 1_q_rd) == "1 rd");
     CHECK(STD_FMT::format("{}", 1_q_thou) == "1 thou");