From 9a49df7222f22df308dfa1e6614932c729627af3 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Tue, 8 Sep 2020 21:17:09 +0200
Subject: [PATCH] refactor: :boom: `Scalar` concept renamed to `ScalableNumber`

Resolves #114
---
 docs/design/quantity.rst                       | 12 ++++++------
 docs/framework/constants.rst                   |  4 ++--
 docs/framework/dimensions.rst                  | 10 +++++-----
 docs/framework/quantities.rst                  |  9 +++++----
 docs/glossary.rst                              |  2 +-
 docs/use_cases/custom_representation_types.rst | 14 +++++++-------
 docs/use_cases/extensions.rst                  |  6 +++---
 docs_disabled/reference/core/concepts.rst      |  2 +-
 example/glide_computer.cpp                     |  4 ++--
 example/linear_algebra.cpp                     |  6 +++---
 example/measurement.cpp                        |  2 +-
 src/include/units/bits/common_quantity.h       |  6 +++---
 src/include/units/concepts.h                   |  4 ++--
 src/include/units/customization_points.h       |  4 ++--
 src/include/units/data/bitrate.h               |  2 +-
 src/include/units/data/information.h           |  2 +-
 src/include/units/dimensionless.h              |  2 +-
 src/include/units/physical/cgs/acceleration.h  |  2 +-
 src/include/units/physical/cgs/area.h          |  2 +-
 src/include/units/physical/cgs/energy.h        |  2 +-
 src/include/units/physical/cgs/force.h         |  2 +-
 src/include/units/physical/cgs/length.h        |  2 +-
 src/include/units/physical/cgs/mass.h          |  2 +-
 src/include/units/physical/cgs/power.h         |  2 +-
 src/include/units/physical/cgs/pressure.h      |  2 +-
 src/include/units/physical/cgs/speed.h         |  2 +-
 src/include/units/physical/fps/acceleration.h  |  2 +-
 src/include/units/physical/fps/area.h          |  2 +-
 src/include/units/physical/fps/density.h       |  2 +-
 src/include/units/physical/fps/energy.h        |  2 +-
 src/include/units/physical/fps/force.h         |  2 +-
 src/include/units/physical/fps/length.h        |  2 +-
 src/include/units/physical/fps/mass.h          |  2 +-
 src/include/units/physical/fps/power.h         |  2 +-
 src/include/units/physical/fps/pressure.h      |  2 +-
 src/include/units/physical/fps/speed.h         |  2 +-
 src/include/units/physical/fps/volume.h        |  2 +-
 src/include/units/physical/natural/constants.h |  2 +-
 .../units/physical/natural/dimensions.h        | 16 ++++++++--------
 src/include/units/physical/si/absorbed_dose.h  |  2 +-
 src/include/units/physical/si/acceleration.h   |  2 +-
 src/include/units/physical/si/angle.h          |  2 +-
 .../units/physical/si/angular_velocity.h       |  2 +-
 src/include/units/physical/si/area.h           |  2 +-
 src/include/units/physical/si/capacitance.h    |  2 +-
 .../units/physical/si/catalytic_activity.h     |  2 +-
 src/include/units/physical/si/charge_density.h |  4 ++--
 src/include/units/physical/si/concentration.h  |  2 +-
 src/include/units/physical/si/conductance.h    |  2 +-
 src/include/units/physical/si/constants.h      | 18 +++++++++---------
 src/include/units/physical/si/current.h        |  2 +-
 .../units/physical/si/current_density.h        |  2 +-
 src/include/units/physical/si/density.h        |  2 +-
 .../units/physical/si/dynamic_viscosity.h      |  2 +-
 .../units/physical/si/electric_charge.h        |  2 +-
 .../physical/si/electric_field_strength.h      |  2 +-
 src/include/units/physical/si/energy.h         |  2 +-
 src/include/units/physical/si/force.h          |  2 +-
 src/include/units/physical/si/frequency.h      |  2 +-
 src/include/units/physical/si/heat_capacity.h  |  6 +++---
 src/include/units/physical/si/inductance.h     |  2 +-
 src/include/units/physical/si/length.h         |  2 +-
 src/include/units/physical/si/luminance.h      |  2 +-
 .../units/physical/si/luminous_intensity.h     |  2 +-
 src/include/units/physical/si/magnetic_flux.h  |  2 +-
 .../units/physical/si/magnetic_induction.h     |  2 +-
 src/include/units/physical/si/mass.h           |  2 +-
 src/include/units/physical/si/molar_energy.h   |  2 +-
 src/include/units/physical/si/momentum.h       |  2 +-
 src/include/units/physical/si/permeability.h   |  2 +-
 src/include/units/physical/si/permittivity.h   |  2 +-
 src/include/units/physical/si/power.h          |  2 +-
 src/include/units/physical/si/pressure.h       |  2 +-
 src/include/units/physical/si/resistance.h     |  2 +-
 src/include/units/physical/si/speed.h          |  2 +-
 src/include/units/physical/si/substance.h      |  2 +-
 .../units/physical/si/surface_tension.h        |  2 +-
 src/include/units/physical/si/temperature.h    |  2 +-
 .../units/physical/si/thermal_conductivity.h   |  2 +-
 src/include/units/physical/si/time.h           |  2 +-
 src/include/units/physical/si/torque.h         |  2 +-
 src/include/units/physical/si/voltage.h        |  2 +-
 src/include/units/physical/si/volume.h         |  2 +-
 src/include/units/quantity.h                   | 16 ++++++++--------
 src/include/units/quantity_cast.h              |  6 +++---
 src/include/units/quantity_point.h             |  2 +-
 .../static/custom_rep_min_req_test.cpp         | 10 +++++-----
 test/unit_test/static/custom_unit_test.cpp     |  4 ++--
 88 files changed, 149 insertions(+), 148 deletions(-)

diff --git a/docs/design/quantity.rst b/docs/design/quantity.rst
index a027d62a..a777898c 100644
--- a/docs/design/quantity.rst
+++ b/docs/design/quantity.rst
@@ -11,7 +11,7 @@ Interface
 The difference is that it uses ``double`` as a default representation and has
 a few additional member types and functions::
 
-    template<Dimension D, UnitOf<D> U, Scalar Rep = double>
+    template<Dimension D, UnitOf<D> U, ScalableNumber Rep = double>
     class quantity {
     public:
       using dimension = D;
@@ -24,23 +24,23 @@ a few additional member types and functions::
 
     template<typename D1, typename U1, typename Rep1, typename D2, typename U2, typename Rep2>
       requires detail::basic_arithmetic<Rep1, Rep2> && equivalent_dim<D1, dim_invert<D2>>
-    [[nodiscard]] constexpr Scalar auto operator*(const quantity<D1, U1, Rep1>& lhs,
-                                                  const quantity<D2, U2, Rep2>& rhs);
+    [[nodiscard]] constexpr ScalableNumber auto operator*(const quantity<D1, U1, Rep1>& lhs,
+                                                          const quantity<D2, U2, Rep2>& rhs);
 
     template<typename D1, typename U1, typename Rep1, typename D2, typename U2, typename Rep2>
       requires detail::basic_arithmetic<Rep1, Rep2> && (!equivalent_dim<D1, dim_invert<D2>>)
     [[nodiscard]] constexpr Quantity auto operator*(const quantity<D1, U1, Rep1>& lhs,
                                                     const quantity<D2, U2, Rep2>& rhs);
 
-    template<Scalar Value, typename D, typename U, typename Rep>
+    template<ScalableNumber Value, typename D, typename U, typename Rep>
       requires std::magma<std::ranges::divided_by, Value, Rep>
     [[nodiscard]] constexpr Quantity auto operator/(const Value& v,
                                                     const quantity<D, U, Rep>& q);
 
     template<typename D1, typename U1, typename Rep1, typename D2, typename U2, typename Rep2>
       requires detail::basic_arithmetic<Rep1, Rep2> && equivalent_dim<D1, D2>
-    [[nodiscard]] constexpr Scalar auto operator/(const quantity<D1, U1, Rep1>& lhs,
-                                                  const quantity<D2, U2, Rep2>& rhs);
+    [[nodiscard]] constexpr ScalableNumber auto operator/(const quantity<D1, U1, Rep1>& lhs,
+                                                          const quantity<D2, U2, Rep2>& rhs);
 
     template<typename D1, typename U1, typename Rep1, typename D2, typename U2, typename Rep2>
       requires detail::basic_arithmetic<Rep1, Rep2> && (!equivalent_dim<D1, D2>)
diff --git a/docs/framework/constants.rst b/docs/framework/constants.rst
index 95336190..dfc070f3 100644
--- a/docs/framework/constants.rst
+++ b/docs/framework/constants.rst
@@ -18,7 +18,7 @@ For example the speed of light constant in :term:`SI` is defined as::
 
     namespace si::si2019 {
 
-    template<Scalar Rep = double>
+    template<ScalableNumber Rep = double>
     inline constexpr auto speed_of_light = speed<metre_per_second, Rep>(299792458);
 
     }
@@ -27,7 +27,7 @@ The same constant defined for natural units may be provided as::
 
     namespace natural {
 
-    template<Scalar Rep = double>
+    template<ScalableNumber Rep = double>
     inline constexpr auto speed_of_light = speed<unitless, Rep>(1);
 
     }
diff --git a/docs/framework/dimensions.rst b/docs/framework/dimensions.rst
index 017a8b3a..6fae1125 100644
--- a/docs/framework/dimensions.rst
+++ b/docs/framework/dimensions.rst
@@ -23,7 +23,7 @@ each other and the result will always be a quantity of the same dimension:
     Length auto res2 = dist1 - dist2;
 
 Additionally, we can always multiply or divide a quantity by a
-:term:`scalar` and in such a case the quantity's dimension will also
+:term:`scalable number` and in such a case the quantity's dimension will also
 not change:
 
 .. code-block::
@@ -35,7 +35,7 @@ not change:
     Length auto res3 = res2 / 2;   // 6 m
 
 However, if we try to multiply or divide quantities of the same or
-different dimensions, or we will divide a scalar by a quantity, we most
+different dimensions, or we will divide a scalable number by a quantity, we most
 probably will always end up in a quantity of a yet another dimension:
 
 .. code-block::
@@ -50,7 +50,7 @@ probably will always end up in a quantity of a yet another dimension:
 
 However, please note that there is an exception from the above rule.
 In case we divide the same dimensions, or multiply by the inverted
-dimension, than we will end up with just a scalar type:
+dimension, than we will end up with just a scalable number type:
 
 .. code-block::
     :emphasize-lines: 4-5
@@ -58,8 +58,8 @@ dimension, than we will end up with just a scalar type:
     Time auto dur1 = 10q_s;
     Time auto dur2 = 2q_s;
     Frequency auto fr1 = 5q_Hz;
-    Scalar auto v1 = dur1 / dur2;    // 5
-    Scalar auto v2 = dur1 * fr1;     // 50
+    ScalableNumber auto v1 = dur1 / dur2;    // 5
+    ScalableNumber auto v2 = dur1 * fr1;     // 50
 
 Quantity points have a more restricted set of operations.
 Quantity points can't be added together,
diff --git a/docs/framework/quantities.rst b/docs/framework/quantities.rst
index b5723ab8..2e2e6fd0 100644
--- a/docs/framework/quantities.rst
+++ b/docs/framework/quantities.rst
@@ -11,7 +11,7 @@ with a specific representation and is represented in the library with a
 Quantity Construction
 ---------------------
 
-To create the quantity object from a :term:`scalar` we just have to pass
+To create the quantity object from a :term:`scalable number` we just have to pass
 the value to the `quantity` class template explicit constructor::
 
     quantity<si::dim_length, si::kilometre, double> d(123);
@@ -33,7 +33,7 @@ type to ``double`` by default::
 
     namespace si {
 
-    template<Unit U, Scalar Rep = double>
+    template<Unit U, ScalableNumber Rep = double>
     using length = quantity<dim_length, U, Rep>;
 
     }
@@ -73,7 +73,8 @@ be used::
 
     All instances of `quantity` class always match the `Quantity` concept.
     All other regular types that are not quantities are called
-    :term:`scalars <scalar>` by the library and match the `Scalar` concept.
+    :term:`scalable numbers <scalable number>` by the library and match the
+    `ScalableNumber` concept.
 
 However, the above is not the most important usage of those concepts. Let's
 assume that the user wants to implement an ``avg_speed`` function that will
@@ -183,7 +184,7 @@ are provided::
     template<typename T>
     concept Dimensionless = QuantityOf<T, dim_one>;
 
-    template<Unit U, Scalar Rep = double>
+    template<Unit U, ScalableNumber Rep = double>
     using dimensionless = quantity<dim_one, U, Rep>;
 
 There are two special units provided for usage with such a quantity:
diff --git a/docs/glossary.rst b/docs/glossary.rst
index e729ad65..cc9f4def 100644
--- a/docs/glossary.rst
+++ b/docs/glossary.rst
@@ -198,7 +198,7 @@ Other definitions
       - The order and types of dimensions used in the recipe determine how an unnamed
         dimension's unit symbol is being printed in the text output
 
-    scalar
+    scalable number
       - Not a `quantity`
       - Can be passed as a representation type to the :class:`units::quantity` type or be used as a factor
         while multiplying or dividing a `quantity`.
diff --git a/docs/use_cases/custom_representation_types.rst b/docs/use_cases/custom_representation_types.rst
index f7ba006c..f650a0f3 100644
--- a/docs/use_cases/custom_representation_types.rst
+++ b/docs/use_cases/custom_representation_types.rst
@@ -9,11 +9,11 @@ its own custom logic for it (i.e. use a complex number or a measurement class th
 not only a value but also a measurement error).
 
 
-A `Scalar` concept
-------------------
+A `ScalableNumber` concept
+--------------------------
 
 To support a minimum set of `quantity` operations all custom representation types have to
-satisfy at least the `Scalar` concept. Which means that they:
+satisfy at least the `ScalableNumber` concept. Which means that they:
 
 - cannot be quantities by themselves,
 - cannot be wrappers over the `quantity` type (i.e. ``std::optional<si::length<si::metre>>``),
@@ -101,8 +101,8 @@ The only difference here is that in this case we have to explicitly cast the `qu
 Additional Requirements
 -----------------------
 
-As noted in the previous chapter, the `Scalar` concept guarantees us the possibility to
-construct quantities, convert between the units of the same dimension, and compare them
+As noted in the previous chapter, the `ScalableNumber` concept guarantees us the possibility
+to construct quantities, convert between the units of the same dimension, and compare them
 for equality. To provide additional `quantity` operations the custom representation type
 have to satisfy more requirements.
 
@@ -200,7 +200,7 @@ The `quantity` class template has a few static member functions: `quantity::zero
 representation type. The default implementation is provided through the `quantity_values` class
 template::
 
-    template<Scalar Rep>
+    template<ScalableNumber Rep>
     struct quantity_values {
       static constexpr Rep zero() noexcept { return Rep(0); }
       static constexpr Rep one() noexcept { return Rep(1); }
@@ -220,7 +220,7 @@ library's framework treat floating-point representation types differently than t
 ones. This behavior can also be extended to the custom representation types with
 `treat_as_floating_point` customization point which default definition is::
 
-    template<Scalar Rep>
+    template<ScalableNumber Rep>
     inline constexpr bool treat_as_floating_point = std::is_floating_point_v<Rep>;
 
 If our representation type should have a floating-point semantics or if it is a class
diff --git a/docs/use_cases/extensions.rst b/docs/use_cases/extensions.rst
index 52ca9ffd..2df24018 100644
--- a/docs/use_cases/extensions.rst
+++ b/docs/use_cases/extensions.rst
@@ -121,7 +121,7 @@ coherent unit::
     struct desk_per_hour : deduced_unit<desk_per_hour, dim_desk_rate, desk, si::hour> {};
 
     // a quantity of our dimension
-    template<Unit U, Scalar Rep = double>
+    template<Unit U, ScalableNumber Rep = double>
     using desk_rate = quantity<dim_desk_rate, U, Rep>;
 
     // a concept matching the above quantity
@@ -150,7 +150,7 @@ define a new base dimension, its units, quantity helper, concept, and UDLs::
     struct person : named_unit<person, "person", no_prefix> {};
     struct dim_people : base_dimension<"people", person> {};
 
-    template<Unit U, Scalar Rep = double>
+    template<Unit U, ScalableNumber Rep = double>
     using people = quantity<dim_people, U, Rep>;
 
     template<typename T>
@@ -169,7 +169,7 @@ With the above we can now define a new derived dimension::
 
     struct person_per_desk : deduced_unit<person_per_desk, dim_occupancy_rate, person, desk> {};
 
-    template<Unit U, Scalar Rep = double>
+    template<Unit U, ScalableNumber Rep = double>
     using occupancy_rate = quantity<dim_occupancy_rate, U, Rep>;
 
     template<typename T>
diff --git a/docs_disabled/reference/core/concepts.rst b/docs_disabled/reference/core/concepts.rst
index 3debd481..747f47c9 100644
--- a/docs_disabled/reference/core/concepts.rst
+++ b/docs_disabled/reference/core/concepts.rst
@@ -63,7 +63,7 @@ Concepts
     satisfy :expr:`Quantity<typename T::value_type>` recursively
     (i.e. :expr:`std::optional<si::length<si::metre>>`).
 
-.. concept:: template<typename T> Scalar
+.. concept:: template<typename T> ScalableNumber
 
     A concept matching non-Quantity types. Satisfied by types that match
     :expr:`(!Quantity<T>) && (!WrappedQuantity<T>) && std::regular<T>` and satisfy one of the
diff --git a/example/glide_computer.cpp b/example/glide_computer.cpp
index 76f68167..36d2840e 100644
--- a/example/glide_computer.cpp
+++ b/example/glide_computer.cpp
@@ -87,7 +87,7 @@ public:
   }
 
   template<typename V>
-    requires (Scalar<V> || Dimensionless<V>)
+    requires (ScalableNumber<V> || Dimensionless<V>)
   [[nodiscard]] friend constexpr auto operator*(const vector& lhs, const V& value)
     requires requires { lhs.magnitude() * value; }
   {
@@ -95,7 +95,7 @@ public:
   }
 
   template<typename V>
-    requires (Scalar<V> || Dimensionless<V>)
+    requires (ScalableNumber<V> || Dimensionless<V>)
   [[nodiscard]] friend constexpr auto operator*(const V& value, const vector& rhs)
     requires requires { value * rhs.magnitude(); }
   {
diff --git a/example/linear_algebra.cpp b/example/linear_algebra.cpp
index 24a0be07..e2506fac 100644
--- a/example/linear_algebra.cpp
+++ b/example/linear_algebra.cpp
@@ -200,10 +200,10 @@ void matrix_of_quantity_tests()
   matrix_of_quantity_divide_by_scalar();
 }
 
-template<units::Unit U = si::metre, units::Scalar Rep = double>
+template<units::Unit U = si::metre, units::ScalableNumber Rep = double>
 using length_v = si::length<U, vector<Rep>>;
 
-template<units::Unit U = si::newton, units::Scalar Rep = double>
+template<units::Unit U = si::newton, units::ScalableNumber Rep = double>
 using force_v = si::force<U, vector<Rep>>;
 
 void quantity_of_vector_add()
@@ -273,7 +273,7 @@ void quantity_of_vector_tests()
   quantity_of_vector_divide_by_scalar();
 }
 
-template<units::Unit U = si::metre, units::Scalar Rep = double>
+template<units::Unit U = si::metre, units::ScalableNumber Rep = double>
 using length_m = si::length<U, matrix<Rep>>;
 
 void quantity_of_matrix_add()
diff --git a/example/measurement.cpp b/example/measurement.cpp
index 1237e7fc..ce1d2b73 100644
--- a/example/measurement.cpp
+++ b/example/measurement.cpp
@@ -114,7 +114,7 @@ private:
   value_type uncertainty_{};
 };
 
-static_assert(units::Scalar<measurement<double>>);
+static_assert(units::ScalableNumber<measurement<double>>);
 
 }  // namespace
 
diff --git a/src/include/units/bits/common_quantity.h b/src/include/units/bits/common_quantity.h
index 20304e83..803dfc7c 100644
--- a/src/include/units/bits/common_quantity.h
+++ b/src/include/units/bits/common_quantity.h
@@ -26,10 +26,10 @@
 
 namespace units {
 
-template<Dimension D, UnitOf<D> U, Scalar Rep>
+template<Dimension D, UnitOf<D> U, ScalableNumber Rep>
 class quantity;
 
-template<Dimension D, UnitOf<D> U, Scalar Rep>
+template<Dimension D, UnitOf<D> U, ScalableNumber Rep>
 class quantity_point;
 
 namespace detail {
@@ -65,7 +65,7 @@ quantity_point<D, U, Rep> common_quantity_point_impl(quantity<D, U, Rep>);
 
 }  // namespace detail
 
-template<Quantity Q1, Quantity Q2, Scalar Rep = std::common_type_t<typename Q1::rep, typename Q2::rep>>
+template<Quantity Q1, Quantity Q2, ScalableNumber Rep = std::common_type_t<typename Q1::rep, typename Q2::rep>>
   requires equivalent_dim<typename Q1::dimension, typename Q2::dimension>
 using common_quantity = TYPENAME detail::common_quantity_impl<Q1, Q2, Rep>::type;
 
diff --git a/src/include/units/concepts.h b/src/include/units/concepts.h
index 43e95eed..6a6da384 100644
--- a/src/include/units/concepts.h
+++ b/src/include/units/concepts.h
@@ -250,7 +250,7 @@ inline constexpr bool is_wrapped_quantity<T> = Quantity<typename T::value_type>
 template<typename T>
 concept WrappedQuantity = detail::is_wrapped_quantity<T>;
 
-// Scalar
+// ScalableNumber
 
 namespace detail {
 
@@ -280,7 +280,7 @@ concept not_constructible_from_integral =
  * Satisfied by types that satisfy `(!Quantity<T>) && (!WrappedQuantity<T>) && std::regular<T>`.
  */
 template<typename T>
-concept Scalar =
+concept ScalableNumber =
   (!Quantity<T>) &&
   (!WrappedQuantity<T>) &&
   std::regular<T> &&
diff --git a/src/include/units/customization_points.h b/src/include/units/customization_points.h
index 5ff0306d..4a9f0dc2 100644
--- a/src/include/units/customization_points.h
+++ b/src/include/units/customization_points.h
@@ -37,7 +37,7 @@ namespace units {
  * 
  * @tparam Rep a representation type for which a type trait is defined
  */
-template<Scalar Rep>
+template<ScalableNumber Rep>
 inline constexpr bool treat_as_floating_point = std::is_floating_point_v<Rep>;
 
 /**
@@ -49,7 +49,7 @@ inline constexpr bool treat_as_floating_point = std::is_floating_point_v<Rep>;
  * 
  * @tparam Rep a representation type for which a type trait is defined
  */
-template<Scalar Rep>
+template<ScalableNumber Rep>
 struct quantity_values {
   static constexpr Rep zero() noexcept { return Rep(0); }
   static constexpr Rep one() noexcept { return Rep(1); }
diff --git a/src/include/units/data/bitrate.h b/src/include/units/data/bitrate.h
index 13a3078d..0709cde6 100644
--- a/src/include/units/data/bitrate.h
+++ b/src/include/units/data/bitrate.h
@@ -41,7 +41,7 @@ struct pebibit_per_second : deduced_unit<pebibit_per_second, dim_bitrate, pebibi
 template<typename T>
 concept Bitrate = QuantityOf<T, dim_bitrate>;
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using bitrate = quantity<dim_bitrate, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/data/information.h b/src/include/units/data/information.h
index 0828f71e..9995f9c8 100644
--- a/src/include/units/data/information.h
+++ b/src/include/units/data/information.h
@@ -48,7 +48,7 @@ struct dim_information : base_dimension<"information", bit> {};
 template<typename T>
 concept Information = QuantityOf<T, dim_information>;
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using information = quantity<dim_information, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/dimensionless.h b/src/include/units/dimensionless.h
index 5228c63b..02e36307 100644
--- a/src/include/units/dimensionless.h
+++ b/src/include/units/dimensionless.h
@@ -40,7 +40,7 @@ struct dim_one : derived_dimension<dim_one, unitless> {};
 template<typename T>
 concept Dimensionless = QuantityOf<T, dim_one>;
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using dimensionless = quantity<dim_one, U, Rep>;
 
 }  // namespace units
diff --git a/src/include/units/physical/cgs/acceleration.h b/src/include/units/physical/cgs/acceleration.h
index c3609212..7c066ad3 100644
--- a/src/include/units/physical/cgs/acceleration.h
+++ b/src/include/units/physical/cgs/acceleration.h
@@ -31,7 +31,7 @@ namespace units::physical::cgs {
 struct gal : named_unit<gal, "Gal", si::prefix> {};
 struct dim_acceleration : physical::dim_acceleration<dim_acceleration, gal, dim_length, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using acceleration = quantity<dim_acceleration, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/cgs/area.h b/src/include/units/physical/cgs/area.h
index 1f52edab..bd4e7f0e 100644
--- a/src/include/units/physical/cgs/area.h
+++ b/src/include/units/physical/cgs/area.h
@@ -33,7 +33,7 @@ using si::square_centimetre;
 
 struct dim_area : physical::dim_area<dim_area, square_centimetre, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using area = quantity<dim_area, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/cgs/energy.h b/src/include/units/physical/cgs/energy.h
index 9c290898..ef881bac 100644
--- a/src/include/units/physical/cgs/energy.h
+++ b/src/include/units/physical/cgs/energy.h
@@ -33,7 +33,7 @@ struct erg : named_unit<erg, "erg", si::prefix> {};
 
 struct dim_energy : physical::dim_energy<dim_energy, erg, dim_force, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using energy = quantity<dim_energy, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/cgs/force.h b/src/include/units/physical/cgs/force.h
index ec3e2d7e..9b9b8ead 100644
--- a/src/include/units/physical/cgs/force.h
+++ b/src/include/units/physical/cgs/force.h
@@ -34,7 +34,7 @@ struct dyne : named_unit<dyne, "dyn", si::prefix> {};
 
 struct dim_force : physical::dim_force<dim_force, dyne, dim_mass, dim_acceleration> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using force = quantity<dim_force, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/cgs/length.h b/src/include/units/physical/cgs/length.h
index c5d82468..11092bb7 100644
--- a/src/include/units/physical/cgs/length.h
+++ b/src/include/units/physical/cgs/length.h
@@ -32,7 +32,7 @@ using si::centimetre;
 
 struct dim_length : physical::dim_length<centimetre> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using length = quantity<dim_length, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/cgs/mass.h b/src/include/units/physical/cgs/mass.h
index 1ad0456b..5079dea8 100644
--- a/src/include/units/physical/cgs/mass.h
+++ b/src/include/units/physical/cgs/mass.h
@@ -32,7 +32,7 @@ using si::gram;
 
 struct dim_mass : physical::dim_mass<gram> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using mass = quantity<dim_mass, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/cgs/power.h b/src/include/units/physical/cgs/power.h
index 6a1c9c2e..a2e1d0e3 100644
--- a/src/include/units/physical/cgs/power.h
+++ b/src/include/units/physical/cgs/power.h
@@ -33,7 +33,7 @@ struct erg_per_second : unit<erg_per_second> {};
 
 struct dim_power : physical::dim_power<dim_power, erg_per_second, dim_energy, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using power = quantity<dim_power, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/cgs/pressure.h b/src/include/units/physical/cgs/pressure.h
index 0c07b3dc..cadd94e3 100644
--- a/src/include/units/physical/cgs/pressure.h
+++ b/src/include/units/physical/cgs/pressure.h
@@ -34,7 +34,7 @@ struct barye : named_unit<barye, "Ba", si::prefix> {};
 
 struct dim_pressure : physical::dim_pressure<dim_pressure, barye, dim_force, dim_area> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using pressure = quantity<dim_pressure, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/cgs/speed.h b/src/include/units/physical/cgs/speed.h
index 5c07f202..f382daa1 100644
--- a/src/include/units/physical/cgs/speed.h
+++ b/src/include/units/physical/cgs/speed.h
@@ -32,7 +32,7 @@ namespace units::physical::cgs {
 struct centimetre_per_second : unit<centimetre_per_second> {};
 struct dim_speed : physical::dim_speed<dim_speed, centimetre_per_second, dim_length, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using speed = quantity<dim_speed, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/fps/acceleration.h b/src/include/units/physical/fps/acceleration.h
index 7d7ef0fb..6917dcdd 100644
--- a/src/include/units/physical/fps/acceleration.h
+++ b/src/include/units/physical/fps/acceleration.h
@@ -31,7 +31,7 @@ namespace units::physical::fps {
 struct foot_per_second_sq : unit<foot_per_second_sq> {};
 struct dim_acceleration : physical::dim_acceleration<dim_acceleration, foot_per_second_sq, dim_length, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using acceleration = quantity<dim_acceleration, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/fps/area.h b/src/include/units/physical/fps/area.h
index d5b7276e..107f053d 100644
--- a/src/include/units/physical/fps/area.h
+++ b/src/include/units/physical/fps/area.h
@@ -33,7 +33,7 @@ struct square_foot : unit<square_foot> {};
 struct dim_area : physical::dim_area<dim_area, square_foot, dim_length> {};
 
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using area = quantity<dim_area, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/fps/density.h b/src/include/units/physical/fps/density.h
index 91f8d58f..118c05b5 100644
--- a/src/include/units/physical/fps/density.h
+++ b/src/include/units/physical/fps/density.h
@@ -33,7 +33,7 @@ struct pound_per_foot_cub : unit<pound_per_foot_cub> {};
 
 struct dim_density : physical::dim_density<dim_density, pound_per_foot_cub, dim_mass, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using density = quantity<dim_density, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/fps/energy.h b/src/include/units/physical/fps/energy.h
index d3bdd14e..2d7f89d8 100644
--- a/src/include/units/physical/fps/energy.h
+++ b/src/include/units/physical/fps/energy.h
@@ -39,7 +39,7 @@ struct foot_pound_force : noble_deduced_unit<foot_pound_force, dim_energy, pound
 
 
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using energy = quantity<dim_energy, U, Rep>;
 
 
diff --git a/src/include/units/physical/fps/force.h b/src/include/units/physical/fps/force.h
index 47a49c16..ad6b32c3 100644
--- a/src/include/units/physical/fps/force.h
+++ b/src/include/units/physical/fps/force.h
@@ -43,7 +43,7 @@ struct kip : alias_unit<kilopound_force, "klbf", no_prefix> {};
 
 struct dim_force : physical::dim_force<dim_force, poundal, dim_mass, dim_acceleration> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using force = quantity<dim_force, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/fps/length.h b/src/include/units/physical/fps/length.h
index d875ecd1..31f46020 100644
--- a/src/include/units/physical/fps/length.h
+++ b/src/include/units/physical/fps/length.h
@@ -52,7 +52,7 @@ struct nautical_mile : named_scaled_unit<nautical_mile, "mi(naut)", no_prefix, r
 
 struct dim_length : physical::dim_length<foot> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using length = quantity<dim_length, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/fps/mass.h b/src/include/units/physical/fps/mass.h
index 80787d1b..3802035f 100644
--- a/src/include/units/physical/fps/mass.h
+++ b/src/include/units/physical/fps/mass.h
@@ -33,7 +33,7 @@ struct pound : named_scaled_unit<pound, "lb", no_prefix, ratio(45'359'237, 100'0
 
 struct dim_mass : physical::dim_mass<pound> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using mass = quantity<dim_mass, U, Rep>;
 
 struct grain : named_scaled_unit<grain, "gr", no_prefix, ratio(1, 7000), pound>{};
diff --git a/src/include/units/physical/fps/power.h b/src/include/units/physical/fps/power.h
index c2142e9a..6a6a320f 100644
--- a/src/include/units/physical/fps/power.h
+++ b/src/include/units/physical/fps/power.h
@@ -37,7 +37,7 @@ struct foot_pound_force_per_second : deduced_unit<foot_pound_force_per_second, d
 
 struct horse_power : named_scaled_unit<horse_power, "hp", no_prefix, ratio(550), foot_pound_force_per_second> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using power = quantity<dim_power, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/fps/pressure.h b/src/include/units/physical/fps/pressure.h
index 36f4d555..a9760bc9 100644
--- a/src/include/units/physical/fps/pressure.h
+++ b/src/include/units/physical/fps/pressure.h
@@ -34,7 +34,7 @@ struct poundal_per_foot_sq : unit<poundal_per_foot_sq> {};
 
 struct dim_pressure : physical::dim_pressure<dim_pressure, poundal_per_foot_sq, dim_force, dim_area> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber 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> {};
diff --git a/src/include/units/physical/fps/speed.h b/src/include/units/physical/fps/speed.h
index d1512a0b..8de37c0a 100644
--- a/src/include/units/physical/fps/speed.h
+++ b/src/include/units/physical/fps/speed.h
@@ -32,7 +32,7 @@ namespace units::physical::fps {
 struct foot_per_second : unit<foot_per_second> {};
 struct dim_speed : physical::dim_speed<dim_speed, foot_per_second, dim_length, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using speed = quantity<dim_speed, U, Rep>;
 
 struct mile_per_hour : deduced_unit<mile_per_hour, dim_speed, mile, hour>{};
diff --git a/src/include/units/physical/fps/volume.h b/src/include/units/physical/fps/volume.h
index 07b6f5f0..57e49c1a 100644
--- a/src/include/units/physical/fps/volume.h
+++ b/src/include/units/physical/fps/volume.h
@@ -33,7 +33,7 @@ struct dim_volume : physical::dim_volume<dim_volume, cubic_foot, dim_length> {};
 
 struct cubic_yard : deduced_unit<cubic_yard, dim_volume, yard> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using volume = quantity<dim_volume, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/natural/constants.h b/src/include/units/physical/natural/constants.h
index afcb89de..20c37379 100644
--- a/src/include/units/physical/natural/constants.h
+++ b/src/include/units/physical/natural/constants.h
@@ -26,7 +26,7 @@
 
 namespace units::physical::natural {
 
-template<Scalar Rep = double>
+template<ScalableNumber Rep = double>
 inline constexpr auto speed_of_light = speed<unitless, Rep>(1);
 
 }  // namespace units::physical::natural
diff --git a/src/include/units/physical/natural/dimensions.h b/src/include/units/physical/natural/dimensions.h
index 4ec305d5..1881f1bb 100644
--- a/src/include/units/physical/natural/dimensions.h
+++ b/src/include/units/physical/natural/dimensions.h
@@ -29,35 +29,35 @@
 namespace units::physical::natural {
 
 struct dim_length : physical::dim_length<inverted_gigaelectronvolt> {};
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using length = quantity<dim_length, U, Rep>;
 
 struct dim_time : physical::dim_time<inverted_gigaelectronvolt> {};
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using time = quantity<dim_time, U, Rep>;
 
 struct dim_mass : physical::dim_mass<gigaelectronvolt> {};
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using mass = quantity<dim_mass, U, Rep>;
 
 struct dim_speed : physical::dim_speed<dim_speed, unitless, dim_length, dim_time> {};
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using speed = quantity<dim_speed, U, Rep>;
 
 struct dim_acceleration : physical::dim_acceleration<dim_acceleration, gigaelectronvolt, dim_length, dim_time> {};
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using acceleration = quantity<dim_acceleration, U, Rep>;
 
 struct dim_force : physical::dim_force<dim_force, square_gigaelectronvolt, dim_mass, dim_acceleration> {};
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using force = quantity<dim_force, U, Rep>;
 
 struct dim_momentum : physical::dim_momentum<dim_momentum, gigaelectronvolt, dim_mass, dim_speed> {};
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using momentum = quantity<dim_momentum, U, Rep>;
 
 struct dim_energy : physical::dim_energy<dim_energy, gigaelectronvolt, dim_force, dim_length> {};
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using energy = quantity<dim_force, U, Rep>;
 
 // Typical UDLs will not work here as the same units are reused by many quantities.
diff --git a/src/include/units/physical/si/absorbed_dose.h b/src/include/units/physical/si/absorbed_dose.h
index 956c8609..9c2e88c5 100644
--- a/src/include/units/physical/si/absorbed_dose.h
+++ b/src/include/units/physical/si/absorbed_dose.h
@@ -54,7 +54,7 @@ struct yottagray : prefixed_unit<yottagray, yotta, gray> {};
 
 struct dim_absorbed_dose : physical::dim_absorbed_dose<dim_absorbed_dose, gray, dim_energy, dim_mass> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using absorbed_dose = quantity<dim_absorbed_dose, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/acceleration.h b/src/include/units/physical/si/acceleration.h
index cdb6bbc5..ca049a35 100644
--- a/src/include/units/physical/si/acceleration.h
+++ b/src/include/units/physical/si/acceleration.h
@@ -31,7 +31,7 @@ namespace units::physical::si {
 struct metre_per_second_sq : unit<metre_per_second_sq> {};
 struct dim_acceleration : physical::dim_acceleration<dim_acceleration, metre_per_second_sq, dim_length, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using acceleration = quantity<dim_acceleration, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/angle.h b/src/include/units/physical/si/angle.h
index e3ecb480..b2114cfb 100644
--- a/src/include/units/physical/si/angle.h
+++ b/src/include/units/physical/si/angle.h
@@ -32,7 +32,7 @@ struct radian : named_unit<radian, "rad", prefix> {};
 
 struct dim_angle : physical::dim_angle<radian> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using angle = quantity<dim_angle, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/angular_velocity.h b/src/include/units/physical/si/angular_velocity.h
index b4825355..924027dc 100644
--- a/src/include/units/physical/si/angular_velocity.h
+++ b/src/include/units/physical/si/angular_velocity.h
@@ -34,7 +34,7 @@ struct radian_per_second : named_unit<radian_per_second, basic_symbol_text{"ω",
 
 struct dim_angular_velocity : physical::dim_angular_velocity<dim_angular_velocity, radian_per_second, dim_angle, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using angular_velocity = quantity<dim_angular_velocity, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/area.h b/src/include/units/physical/si/area.h
index 34fb9f4d..5b11d402 100644
--- a/src/include/units/physical/si/area.h
+++ b/src/include/units/physical/si/area.h
@@ -54,7 +54,7 @@ struct square_yottametre : deduced_unit<square_yottametre, dim_area, yottametre>
 
 struct hectare : alias_unit<square_hectometre, "ha", no_prefix> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using area = quantity<dim_area, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/capacitance.h b/src/include/units/physical/si/capacitance.h
index 640da58c..3287b5fc 100644
--- a/src/include/units/physical/si/capacitance.h
+++ b/src/include/units/physical/si/capacitance.h
@@ -54,7 +54,7 @@ struct yottafarad : prefixed_unit<yottafarad, yotta, farad> {};
 
 struct dim_capacitance : physical::dim_capacitance<dim_capacitance, farad, dim_electric_charge, dim_voltage> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using capacitance = quantity<dim_capacitance, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/catalytic_activity.h b/src/include/units/physical/si/catalytic_activity.h
index 78ad7ca9..a67e9a64 100644
--- a/src/include/units/physical/si/catalytic_activity.h
+++ b/src/include/units/physical/si/catalytic_activity.h
@@ -56,7 +56,7 @@ struct enzyme_unit : named_scaled_unit<enzyme_unit, "U", prefix, ratio(1, 60, -6
 
 struct dim_catalytic_activity : physical::dim_catalytic_activity<dim_catalytic_activity, katal, dim_time, dim_substance> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using catalytic_activity = quantity<dim_catalytic_activity, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/charge_density.h b/src/include/units/physical/si/charge_density.h
index 04ba4a45..0ccad25a 100644
--- a/src/include/units/physical/si/charge_density.h
+++ b/src/include/units/physical/si/charge_density.h
@@ -36,10 +36,10 @@ struct coulomb_per_metre_sq : unit<coulomb_per_metre_sq> {};
 struct dim_charge_density : physical::dim_charge_density<dim_charge_density, coulomb_per_metre_cub, dim_electric_charge, dim_length> {};
 struct dim_surface_charge_density : physical::dim_surface_charge_density<dim_surface_charge_density, coulomb_per_metre_sq, dim_electric_charge, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using charge_density = quantity<dim_charge_density, U, Rep>;
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using surface_charge_density = quantity<dim_surface_charge_density, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/concentration.h b/src/include/units/physical/si/concentration.h
index 4c6c6220..8e85b20c 100644
--- a/src/include/units/physical/si/concentration.h
+++ b/src/include/units/physical/si/concentration.h
@@ -32,7 +32,7 @@ namespace units::physical::si {
 struct mol_per_metre_cub : unit<mol_per_metre_cub> {};
 struct dim_concentration : physical::dim_concentration<dim_concentration, mol_per_metre_cub, dim_substance, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using concentration = quantity<dim_concentration, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/conductance.h b/src/include/units/physical/si/conductance.h
index dd7b16b4..b793d54e 100644
--- a/src/include/units/physical/si/conductance.h
+++ b/src/include/units/physical/si/conductance.h
@@ -49,7 +49,7 @@ struct yottasiemens : prefixed_unit<yottasiemens, yotta, siemens> {};
 
 struct dim_conductance : physical::dim_conductance<dim_conductance, siemens, dim_resistance> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using conductance = quantity<dim_conductance, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/constants.h b/src/include/units/physical/si/constants.h
index 750a1d4b..2a0e0dc0 100644
--- a/src/include/units/physical/si/constants.h
+++ b/src/include/units/physical/si/constants.h
@@ -32,31 +32,31 @@
 
 namespace units::physical::si::si2019 {
 
-template<Scalar Rep = double>
+template<ScalableNumber Rep = double>
 inline constexpr auto planck_constant = energy<joule, Rep>(6.62607015e-34) * time<second, Rep>(1);
 
-template<Scalar Rep = double>
+template<ScalableNumber Rep = double>
 inline constexpr auto reduced_planck_constant = energy<gigaelectronvolt, Rep>(6.582119569e-10) * time<second, Rep>(1);
 
-template<Scalar Rep = double>
+template<ScalableNumber Rep = double>
 inline constexpr auto elementary_charge = electric_charge<coulomb, Rep>(1.602176634e-19);
 
-template<Scalar Rep = double>
+template<ScalableNumber Rep = double>
 inline constexpr auto boltzmann_constant = energy<joule, Rep>(1.380649e-23) / temperature<kelvin, Rep>(1);
 
-template<Scalar Rep = double>
+template<ScalableNumber Rep = double>
 inline constexpr auto avogadro_constant = Rep(6.02214076e23) / substance<mole, Rep>(1);
 
-template<Scalar Rep = double>
+template<ScalableNumber Rep = double>
 inline constexpr auto speed_of_light = speed<metre_per_second, Rep>(299'792'458);
 
-template<Scalar Rep = double>
+template<ScalableNumber Rep = double>
 inline constexpr auto hyperfine_structure_transition_frequency = frequency<hertz, Rep>(9'192'631'770);
 
-// template<Scalar Rep = double>
+// template<ScalableNumber Rep = double>
 // inline constexpr auto luminous_efficacy = 683q_lm / 1q_W;
 
-template<Scalar Rep = double>
+template<ScalableNumber Rep = double>
 inline constexpr auto standard_gravity = acceleration<metre_per_second_sq, Rep>(9.80665);
 
 }  // namespace units::physical::si::si2019
diff --git a/src/include/units/physical/si/current.h b/src/include/units/physical/si/current.h
index b4349006..88e37efd 100644
--- a/src/include/units/physical/si/current.h
+++ b/src/include/units/physical/si/current.h
@@ -52,7 +52,7 @@ struct yottaampere : prefixed_unit<yottaampere, yotta, ampere> {};
 
 struct dim_electric_current : physical::dim_electric_current<ampere> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using current = quantity<dim_electric_current, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/current_density.h b/src/include/units/physical/si/current_density.h
index 157c5cec..19fed28c 100644
--- a/src/include/units/physical/si/current_density.h
+++ b/src/include/units/physical/si/current_density.h
@@ -34,7 +34,7 @@ struct ampere_per_metre_sq : unit<ampere_per_metre_sq> {};
 
 struct dim_current_density : physical::dim_current_density<dim_current_density, ampere_per_metre_sq, dim_electric_current, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using current_density = quantity<dim_current_density, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/density.h b/src/include/units/physical/si/density.h
index 79407611..fa9a1707 100644
--- a/src/include/units/physical/si/density.h
+++ b/src/include/units/physical/si/density.h
@@ -34,7 +34,7 @@ struct kilogram_per_metre_cub : unit<kilogram_per_metre_cub> {};
 
 struct dim_density : physical::dim_density<dim_density, kilogram_per_metre_cub, dim_mass, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using density = quantity<dim_density, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/dynamic_viscosity.h b/src/include/units/physical/si/dynamic_viscosity.h
index 412b4fe3..1a8b7dbb 100644
--- a/src/include/units/physical/si/dynamic_viscosity.h
+++ b/src/include/units/physical/si/dynamic_viscosity.h
@@ -32,7 +32,7 @@ namespace units::physical::si {
 struct pascal_second : unit<pascal_second> {};
 struct dim_dynamic_viscosity : physical::dim_dynamic_viscosity<dim_dynamic_viscosity, pascal_second, dim_pressure, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using dynamic_viscosity = quantity<dim_dynamic_viscosity, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/electric_charge.h b/src/include/units/physical/si/electric_charge.h
index 1bdc153b..60020408 100644
--- a/src/include/units/physical/si/electric_charge.h
+++ b/src/include/units/physical/si/electric_charge.h
@@ -33,7 +33,7 @@ struct coulomb : named_unit<coulomb, "C", prefix> {};
 
 struct dim_electric_charge : physical::dim_electric_charge<dim_electric_charge, coulomb, dim_time, dim_electric_current> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using electric_charge = quantity<dim_electric_charge, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/electric_field_strength.h b/src/include/units/physical/si/electric_field_strength.h
index dead3967..0547d2a3 100644
--- a/src/include/units/physical/si/electric_field_strength.h
+++ b/src/include/units/physical/si/electric_field_strength.h
@@ -31,7 +31,7 @@ namespace units::physical::si {
 struct volt_per_metre : unit<volt_per_metre> {};
 struct dim_electric_field_strength : physical::dim_electric_field_strength<dim_electric_field_strength, volt_per_metre, dim_voltage, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using electric_field_strength = quantity<dim_electric_field_strength, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/energy.h b/src/include/units/physical/si/energy.h
index 6deca407..d18fcd0e 100644
--- a/src/include/units/physical/si/energy.h
+++ b/src/include/units/physical/si/energy.h
@@ -52,7 +52,7 @@ struct gigaelectronvolt : prefixed_unit<gigaelectronvolt, giga, electronvolt> {}
 
 struct dim_energy : physical::dim_energy<dim_energy, joule, dim_force, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using energy = quantity<dim_energy, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/force.h b/src/include/units/physical/si/force.h
index 835b39a9..ce60ad7c 100644
--- a/src/include/units/physical/si/force.h
+++ b/src/include/units/physical/si/force.h
@@ -54,7 +54,7 @@ struct yottanewton : prefixed_unit<yottanewton, yotta, newton> {};
 
 struct dim_force : physical::dim_force<dim_force, newton, dim_mass, dim_acceleration> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using force = quantity<dim_force, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/frequency.h b/src/include/units/physical/si/frequency.h
index c75d8213..b41f4e46 100644
--- a/src/include/units/physical/si/frequency.h
+++ b/src/include/units/physical/si/frequency.h
@@ -48,7 +48,7 @@ struct yottahertz : prefixed_unit<yottahertz, yotta, hertz> {};
 
 struct dim_frequency : physical::dim_frequency<dim_frequency, hertz, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using frequency = quantity<dim_frequency, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/heat_capacity.h b/src/include/units/physical/si/heat_capacity.h
index 87897314..3911dc59 100644
--- a/src/include/units/physical/si/heat_capacity.h
+++ b/src/include/units/physical/si/heat_capacity.h
@@ -39,13 +39,13 @@ struct dim_heat_capacity : physical::dim_heat_capacity<dim_heat_capacity, joule_
 struct dim_specific_heat_capacity : physical::dim_specific_heat_capacity<dim_specific_heat_capacity, joule_per_kilogram_kelvin, dim_heat_capacity, dim_mass> {};
 struct dim_molar_heat_capacity : physical::dim_molar_heat_capacity<dim_molar_heat_capacity, joule_per_mole_kelvin, dim_heat_capacity, dim_substance> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using heat_capacity = quantity<dim_heat_capacity, U, Rep>;
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using specific_heat_capacity = quantity<dim_specific_heat_capacity, U, Rep>;
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using molar_heat_capacity = quantity<dim_molar_heat_capacity, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/inductance.h b/src/include/units/physical/si/inductance.h
index 105a17cb..5a100fa6 100644
--- a/src/include/units/physical/si/inductance.h
+++ b/src/include/units/physical/si/inductance.h
@@ -50,7 +50,7 @@ struct yottahenry : prefixed_unit<yottahenry, yotta, henry> {};
 
 struct dim_inductance : physical::dim_inductance<dim_inductance, henry, dim_magnetic_flux, dim_electric_current> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using inductance = quantity<dim_inductance, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/length.h b/src/include/units/physical/si/length.h
index 34a881b8..c9c7e4be 100644
--- a/src/include/units/physical/si/length.h
+++ b/src/include/units/physical/si/length.h
@@ -54,7 +54,7 @@ struct astronomical_unit : named_scaled_unit<astronomical_unit, "au", no_prefix,
 
 struct dim_length : physical::dim_length<metre> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using length = quantity<dim_length, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/luminance.h b/src/include/units/physical/si/luminance.h
index 2af847c0..1f1be254 100644
--- a/src/include/units/physical/si/luminance.h
+++ b/src/include/units/physical/si/luminance.h
@@ -32,7 +32,7 @@ namespace units::physical::si {
 struct candela_per_metre_sq : unit<candela_per_metre_sq> {};
 struct dim_luminance : physical::dim_luminance<dim_luminance, candela_per_metre_sq, dim_luminous_intensity, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using luminance = quantity<dim_luminance, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/luminous_intensity.h b/src/include/units/physical/si/luminous_intensity.h
index 0cca6300..27396f89 100644
--- a/src/include/units/physical/si/luminous_intensity.h
+++ b/src/include/units/physical/si/luminous_intensity.h
@@ -52,7 +52,7 @@ struct yottacandela : prefixed_unit<yottacandela, yotta, candela> {};
 
 struct dim_luminous_intensity : physical::dim_luminous_intensity<candela> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using luminous_intensity = quantity<dim_luminous_intensity, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/magnetic_flux.h b/src/include/units/physical/si/magnetic_flux.h
index 433db1ee..3d501fbb 100644
--- a/src/include/units/physical/si/magnetic_flux.h
+++ b/src/include/units/physical/si/magnetic_flux.h
@@ -50,7 +50,7 @@ struct yottaweber : prefixed_unit<yottaweber, yotta, weber> {};
 
 struct dim_magnetic_flux : physical::dim_magnetic_flux<dim_magnetic_flux, weber, dim_magnetic_induction, dim_area> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using magnetic_flux = quantity<dim_magnetic_flux, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/magnetic_induction.h b/src/include/units/physical/si/magnetic_induction.h
index 441e67b2..9d631e4e 100644
--- a/src/include/units/physical/si/magnetic_induction.h
+++ b/src/include/units/physical/si/magnetic_induction.h
@@ -54,7 +54,7 @@ struct gauss : named_scaled_unit<gauss, "G", prefix, ratio(1, 10'000), tesla> {}
 
 struct dim_magnetic_induction : physical::dim_magnetic_induction<dim_magnetic_induction, tesla, dim_voltage, dim_time, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using magnetic_induction = quantity<dim_magnetic_induction, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/mass.h b/src/include/units/physical/si/mass.h
index c015e601..8ff950da 100644
--- a/src/include/units/physical/si/mass.h
+++ b/src/include/units/physical/si/mass.h
@@ -76,7 +76,7 @@ struct dalton : named_scaled_unit<dalton, "Da", no_prefix, ratio(16'605'390'666'
 
 struct dim_mass : physical::dim_mass<kilogram> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using mass = quantity<dim_mass, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/molar_energy.h b/src/include/units/physical/si/molar_energy.h
index 6d8b5d64..cbfd44d6 100644
--- a/src/include/units/physical/si/molar_energy.h
+++ b/src/include/units/physical/si/molar_energy.h
@@ -34,7 +34,7 @@ struct joule_per_mole : unit<joule_per_mole> {};
 
 struct dim_molar_energy : physical::dim_molar_energy<dim_molar_energy, joule_per_mole, dim_energy, dim_substance> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using molar_energy = quantity<dim_molar_energy, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/momentum.h b/src/include/units/physical/si/momentum.h
index 0e15dbf6..f8f3d6da 100644
--- a/src/include/units/physical/si/momentum.h
+++ b/src/include/units/physical/si/momentum.h
@@ -32,7 +32,7 @@ namespace units::physical::si {
 struct kilogram_metre_per_second : unit<kilogram_metre_per_second> {};
 struct dim_momentum : physical::dim_momentum<dim_momentum, kilogram_metre_per_second, dim_mass, dim_speed> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using momentum = quantity<dim_momentum, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/permeability.h b/src/include/units/physical/si/permeability.h
index 752acf04..a0bd9640 100644
--- a/src/include/units/physical/si/permeability.h
+++ b/src/include/units/physical/si/permeability.h
@@ -33,7 +33,7 @@ struct henry_per_metre : unit<henry_per_metre> {};
 
 struct dim_permeability : physical::dim_permeability<dim_permeability, henry_per_metre, dim_inductance, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using permeability = quantity<dim_permeability, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/permittivity.h b/src/include/units/physical/si/permittivity.h
index 2f31fc26..151147ca 100644
--- a/src/include/units/physical/si/permittivity.h
+++ b/src/include/units/physical/si/permittivity.h
@@ -33,7 +33,7 @@ struct farad_per_metre : unit<farad_per_metre> {};
 
 struct dim_permittivity : physical::dim_permittivity<dim_permittivity, farad_per_metre, dim_capacitance, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using permittivity = quantity<dim_permittivity, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/power.h b/src/include/units/physical/si/power.h
index 62c95239..42f62a02 100644
--- a/src/include/units/physical/si/power.h
+++ b/src/include/units/physical/si/power.h
@@ -49,7 +49,7 @@ struct yottawatt : prefixed_unit<yottawatt, yotta, watt> {};
 
 struct dim_power : physical::dim_power<dim_power, watt, dim_energy, dim_time> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using power = quantity<dim_power, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/pressure.h b/src/include/units/physical/si/pressure.h
index 6f68ce52..e0903d9d 100644
--- a/src/include/units/physical/si/pressure.h
+++ b/src/include/units/physical/si/pressure.h
@@ -54,7 +54,7 @@ struct yottapascal : prefixed_unit<yottapascal, yotta, pascal> {};
 
 struct dim_pressure : physical::dim_pressure<dim_pressure, pascal, dim_force, dim_area> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using pressure = quantity<dim_pressure, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/resistance.h b/src/include/units/physical/si/resistance.h
index eee8e1cb..4576b977 100644
--- a/src/include/units/physical/si/resistance.h
+++ b/src/include/units/physical/si/resistance.h
@@ -50,7 +50,7 @@ struct yottaohm : prefixed_unit<yottaohm, yotta, ohm> {};
 
 struct dim_resistance : physical::dim_resistance<dim_resistance, ohm, dim_voltage, dim_electric_current> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using resistance = quantity<dim_resistance, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/speed.h b/src/include/units/physical/si/speed.h
index 46ce7189..14f08186 100644
--- a/src/include/units/physical/si/speed.h
+++ b/src/include/units/physical/si/speed.h
@@ -34,7 +34,7 @@ struct dim_speed : physical::dim_speed<dim_speed, metre_per_second, dim_length,
 
 struct kilometre_per_hour : deduced_unit<kilometre_per_hour, dim_speed, kilometre, hour> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using speed = quantity<dim_speed, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/substance.h b/src/include/units/physical/si/substance.h
index a28f51ba..c7706edc 100644
--- a/src/include/units/physical/si/substance.h
+++ b/src/include/units/physical/si/substance.h
@@ -32,7 +32,7 @@ struct mole : named_unit<mole, "mol", prefix> {};
 
 struct dim_substance : physical::dim_substance<mole> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using substance = quantity<dim_substance, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/surface_tension.h b/src/include/units/physical/si/surface_tension.h
index 77befa13..67867061 100644
--- a/src/include/units/physical/si/surface_tension.h
+++ b/src/include/units/physical/si/surface_tension.h
@@ -32,7 +32,7 @@ struct newton_per_metre : unit<newton_per_metre> {};
 
 struct dim_surface_tension : physical::dim_surface_tension<dim_surface_tension, newton_per_metre, dim_force, dim_length> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using surface_tension = quantity<dim_surface_tension, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/temperature.h b/src/include/units/physical/si/temperature.h
index cf016ebc..19fc2ddb 100644
--- a/src/include/units/physical/si/temperature.h
+++ b/src/include/units/physical/si/temperature.h
@@ -31,7 +31,7 @@ struct kelvin : named_unit<kelvin, "K", no_prefix> {};
 
 struct dim_thermodynamic_temperature : physical::dim_thermodynamic_temperature<kelvin> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using temperature = quantity<dim_thermodynamic_temperature, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/thermal_conductivity.h b/src/include/units/physical/si/thermal_conductivity.h
index b74f0b87..ff845792 100644
--- a/src/include/units/physical/si/thermal_conductivity.h
+++ b/src/include/units/physical/si/thermal_conductivity.h
@@ -33,7 +33,7 @@ struct watt_per_metre_kelvin : unit<watt_per_metre_kelvin> {};
 
 struct dim_thermal_conductivity : physical::dim_thermal_conductivity<dim_thermal_conductivity, watt_per_metre_kelvin, dim_power, dim_length, dim_thermodynamic_temperature> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using thermal_conductivity = quantity<dim_thermal_conductivity, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/time.h b/src/include/units/physical/si/time.h
index 5c421f09..f3352295 100644
--- a/src/include/units/physical/si/time.h
+++ b/src/include/units/physical/si/time.h
@@ -43,7 +43,7 @@ struct day : named_scaled_unit<hour, "d", no_prefix, ratio(24), hour> {};
 
 struct dim_time : physical::dim_time<second> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using time = quantity<dim_time, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/torque.h b/src/include/units/physical/si/torque.h
index c6fbe4d8..e5aee85d 100644
--- a/src/include/units/physical/si/torque.h
+++ b/src/include/units/physical/si/torque.h
@@ -34,7 +34,7 @@ struct newton_metre : named_unit<newton_metre, "Nm", prefix> {};
 
 struct dim_torque : physical::dim_torque<dim_torque, newton_metre, dim_energy, dim_angle> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using torque = quantity<dim_torque, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/voltage.h b/src/include/units/physical/si/voltage.h
index b974ddfd..a0e9ee7a 100644
--- a/src/include/units/physical/si/voltage.h
+++ b/src/include/units/physical/si/voltage.h
@@ -54,7 +54,7 @@ struct yottavolt : prefixed_unit<yottavolt, yotta, volt> {};
 
 struct dim_voltage : physical::dim_voltage<dim_voltage, volt, dim_power, dim_electric_current> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using voltage = quantity<dim_voltage, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/physical/si/volume.h b/src/include/units/physical/si/volume.h
index ad5affc8..6d60139c 100644
--- a/src/include/units/physical/si/volume.h
+++ b/src/include/units/physical/si/volume.h
@@ -74,7 +74,7 @@ struct exalitre : prefixed_unit<petalitre, exa, litre> {};
 struct zettalitre : prefixed_alias_unit<cubic_megametre, zetta, litre> {};
 struct yottalitre : prefixed_unit<yottalitre, yotta, litre> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using volume = quantity<dim_volume, U, Rep>;
 
 inline namespace literals {
diff --git a/src/include/units/quantity.h b/src/include/units/quantity.h
index 382b245d..72a5b346 100644
--- a/src/include/units/quantity.h
+++ b/src/include/units/quantity.h
@@ -58,7 +58,7 @@ concept safe_divisible = // exposition only
  * @tparam U a measurement unit of the quantity
  * @tparam Rep a type to be used to represent values of a quantity
  */
-template<Dimension D, UnitOf<D> U, Scalar Rep = double>
+template<Dimension D, UnitOf<D> U, ScalableNumber Rep = double>
 class quantity {
   Rep value_{};
 
@@ -71,7 +71,7 @@ public:
   quantity(const quantity&) = default;
   quantity(quantity&&) = default;
 
-  template<Scalar Value>
+  template<ScalableNumber Value>
     requires detail::safe_convertible<Value, rep>
   constexpr explicit(!(std::is_same_v<dimension, dim_one> && std::is_same_v<unit, unitless>)) quantity(const Value& v) : value_{static_cast<rep>(v)} {}
 
@@ -176,7 +176,7 @@ public:
     return *this;
   }
 
-  template<Scalar Value>
+  template<ScalableNumber Value>
     requires (!treat_as_floating_point<rep>) &&
              (!treat_as_floating_point<Value>)
   constexpr quantity& operator%=(const Value& rhs)
@@ -227,7 +227,7 @@ public:
     return ret(ret(lhs).count() - ret(rhs).count());
   }
 
-  template<Scalar Value>
+  template<ScalableNumber Value>
     requires std::regular_invocable<std::multiplies<>, Rep, Value>
   [[nodiscard]] friend constexpr Quantity auto operator*(const quantity& q, const Value& v)
   {
@@ -236,7 +236,7 @@ public:
     return ret(q.count() * v);
   }
 
-  template<Scalar Value>
+  template<ScalableNumber Value>
     requires std::regular_invocable<std::multiplies<>, Value, Rep>
   [[nodiscard]] friend constexpr Quantity auto operator*(const Value& v, const quantity& q)
   {
@@ -254,7 +254,7 @@ public:
     return ret(lhs.count() * rhs.count());
   }
 
-  template<Scalar Value>
+  template<ScalableNumber Value>
     requires std::regular_invocable<std::divides<>, Value, Rep>
   [[nodiscard]] friend constexpr Quantity auto operator/(const Value& v, const quantity& q)
   {
@@ -267,7 +267,7 @@ public:
     return ret(v / q.count());
   }
 
-  template<Scalar Value>
+  template<ScalableNumber Value>
     requires std::regular_invocable<std::divides<>, Rep, Value>
   [[nodiscard]] friend constexpr Quantity auto operator/(const quantity& q, const Value& v)
   {
@@ -291,7 +291,7 @@ public:
     return ret(lhs.count() / rhs.count());
   }
 
-  template<Scalar Value>
+  template<ScalableNumber Value>
     requires (!treat_as_floating_point<Rep>) &&
             (!treat_as_floating_point<Value>) &&
             std::regular_invocable<std::modulus<>, Rep, Value>
diff --git a/src/include/units/quantity_cast.h b/src/include/units/quantity_cast.h
index d695b671..7700f05b 100644
--- a/src/include/units/quantity_cast.h
+++ b/src/include/units/quantity_cast.h
@@ -36,10 +36,10 @@
 
 namespace units {
 
-template<Dimension D, UnitOf<D> U, Scalar Rep>
+template<Dimension D, UnitOf<D> U, ScalableNumber Rep>
 class quantity;
 
-template<Dimension D, UnitOf<D> U, Scalar Rep>
+template<Dimension D, UnitOf<D> U, ScalableNumber Rep>
 class quantity_point;
 
 namespace detail {
@@ -374,7 +374,7 @@ template<Unit ToU, typename D, typename U, typename Rep>
  *
  * @tparam ToRep a representation type to use for a target quantity
  */
-template<Scalar ToRep, typename D, typename U, typename Rep>
+template<ScalableNumber ToRep, typename D, typename U, typename Rep>
 [[nodiscard]] constexpr auto quantity_cast(const quantity<D, U, Rep>& q)
 {
   return quantity_cast<quantity<D, U, ToRep>>(q);
diff --git a/src/include/units/quantity_point.h b/src/include/units/quantity_point.h
index 3777ef32..5de4ba09 100644
--- a/src/include/units/quantity_point.h
+++ b/src/include/units/quantity_point.h
@@ -37,7 +37,7 @@ namespace units {
  * @tparam U a measurement unit of the quantity point
  * @tparam Rep a type to be used to represent values of a quantity point
  */
-template<Dimension D, UnitOf<D> U, Scalar Rep = double>
+template<Dimension D, UnitOf<D> U, ScalableNumber Rep = double>
 class quantity_point {
 public:
   using quantity_type = quantity<D, U, Rep>;
diff --git a/test/unit_test/static/custom_rep_min_req_test.cpp b/test/unit_test/static/custom_rep_min_req_test.cpp
index 2f50c244..37a38e69 100644
--- a/test/unit_test/static/custom_rep_min_req_test.cpp
+++ b/test/unit_test/static/custom_rep_min_req_test.cpp
@@ -86,7 +86,7 @@ using impl_impl = impl_constructible_impl_convertible<T>;
 
 static_assert(std::convertible_to<float, impl_impl<float>>);
 static_assert(std::convertible_to<impl_impl<float>, float>);
-static_assert(units::Scalar<impl_impl<float>>);
+static_assert(units::ScalableNumber<impl_impl<float>>);
 
 template<typename T>
 struct expl_constructible_impl_convertible : scalar_ops<expl_constructible_impl_convertible<T>> {
@@ -101,7 +101,7 @@ using expl_impl = expl_constructible_impl_convertible<T>;
 
 static_assert(!std::convertible_to<float, expl_impl<float>>);
 static_assert(std::convertible_to<expl_impl<float>, float>);
-static_assert(units::Scalar<expl_impl<float>>);
+static_assert(units::ScalableNumber<expl_impl<float>>);
 
 template<typename T>
 struct impl_constructible_expl_convertible : scalar_ops<impl_constructible_expl_convertible<T>> {
@@ -116,7 +116,7 @@ using impl_expl = impl_constructible_expl_convertible<T>;
 
 static_assert(std::convertible_to<float, impl_expl<float>>);
 static_assert(!std::convertible_to<impl_expl<float>, float>);
-static_assert(units::Scalar<impl_expl<float>>);
+static_assert(units::ScalableNumber<impl_expl<float>>);
 
 template<typename T>
 struct expl_constructible_expl_convertible : scalar_ops<expl_constructible_expl_convertible<T>> {
@@ -131,7 +131,7 @@ using expl_expl = expl_constructible_expl_convertible<T>;
 
 static_assert(!std::convertible_to<float, expl_expl<float>>);
 static_assert(!std::convertible_to<expl_expl<float>, float>);
-static_assert(units::Scalar<expl_expl<float>>);
+static_assert(units::ScalableNumber<expl_expl<float>>);
 
 }  // namespace
 
@@ -170,7 +170,7 @@ using namespace units::physical::si;
 
 // constructors
 
-// Quantity from Scalar
+// Quantity from ScalableNumber
 // int <- int
 static_assert(length<metre, int>(expl_impl<int>(1)).count() == 1);
 static_assert(!std::is_constructible_v<length<metre, int>, impl_expl<int>>);
diff --git a/test/unit_test/static/custom_unit_test.cpp b/test/unit_test/static/custom_unit_test.cpp
index 07ebc27f..bd396f4a 100644
--- a/test/unit_test/static/custom_unit_test.cpp
+++ b/test/unit_test/static/custom_unit_test.cpp
@@ -35,14 +35,14 @@ using namespace units::physical::si;
 struct sq_volt_per_hertz : 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>> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber 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 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>> {};
 
-template<Unit U, Scalar Rep = double>
+template<Unit U, ScalableNumber Rep = double>
 using amplitude_spectral_density = quantity<dim_amplitude_spectral_density, U, Rep>;
 
 }