From 6646051e65453f7425ac87a1284aa079e7d2494f Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Thu, 4 Apr 2019 11:00:40 +0200
Subject: [PATCH] Hand written concepts replaced with Casey Carter's repository

---
 CMakeLists.txt                       |  2 +-
 conanfile.py                         |  2 ++
 example/example.cpp                  |  2 +-
 src/CMakeLists.txt                   |  4 +++
 src/include/units/bits/stdconcepts.h | 48 ----------------------------
 src/include/units/bits/tools.h       |  4 +--
 src/include/units/dimension.h        |  2 +-
 src/include/units/quantity.h         | 17 +++++-----
 src/include/units/si/frequency.h     |  2 +-
 src/include/units/si/length.h        |  2 +-
 src/include/units/si/time.h          |  2 +-
 src/include/units/si/velocity.h      |  2 +-
 src/include/units/unit.h             |  2 +-
 13 files changed, 24 insertions(+), 67 deletions(-)
 delete mode 100644 src/include/units/bits/stdconcepts.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5dd89d06..1d9fe9db 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -30,7 +30,7 @@ list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake/common/cmake")
 include(tools)
 
 # use Conan configuration if available
-conan_init(cmake_paths)
+conan_init(cmake)
 
 # project-specific compilation flags
 include(compile_flags)
diff --git a/conanfile.py b/conanfile.py
index 4fa5de51..5476b79d 100644
--- a/conanfile.py
+++ b/conanfile.py
@@ -30,6 +30,8 @@ class UnitsConan(ConanFile):
     url = "https://github.com/mpusz/units"
     description = "Physical Units library for C++"
     settings = "os", "compiler", "build_type", "arch"
+    requires = ( "cmcstl2/2019.03.18@mpusz/stable" )
+    generators = "cmake"
 
     def build(self):
         cmake = CMake(self)
diff --git a/example/example.cpp b/example/example.cpp
index cfcb101a..d5ec64d7 100644
--- a/example/example.cpp
+++ b/example/example.cpp
@@ -30,7 +30,7 @@ void foo(V v, T t)
 {
   const Length distance = v * t;
   std::cout << "A car driving " << v.count() << " km/h in a time of " << t.count() << " minutes will pass "
-            << quantity_cast<length<meter, int>>(distance).count() << " meters.\n";
+            << quantity_cast<length<meter, double>>(distance).count() << " meters.\n";
 }
 
 void foo()
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 629fa2a0..388721c5 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -48,6 +48,10 @@ add_library(units INTERFACE)
 #    include/units/bits/tools.h
 #)
 target_compile_features(units INTERFACE cxx_std_20)
+target_link_libraries(units
+    INTERFACE
+        CONAN_PKG::cmcstl2
+)
 target_include_directories(units
     INTERFACE
         $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
diff --git a/src/include/units/bits/stdconcepts.h b/src/include/units/bits/stdconcepts.h
deleted file mode 100644
index 88596fe9..00000000
--- a/src/include/units/bits/stdconcepts.h
+++ /dev/null
@@ -1,48 +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.
-
-#pragma once
-
-#include <ratio>
-#include <type_traits>
-
-namespace mp {
-
-  namespace std_concepts {
-
-    template<typename T, typename U>
-    concept bool Same = std::is_same_v<T, U>;
-
-    template<typename From, typename To>
-    concept bool ConvertibleTo =
-      std::is_convertible_v<From, To> &&
-      requires(From (&f)()) {
-        static_cast<To>(f());
-      };
-
-    template<class Derived, class Base>
-    concept bool DerivedFrom =
-      std::is_base_of_v<Base, Derived> &&
-      std::is_convertible_v<const volatile Derived*, const volatile Base*>;
-
-  }  // namespace std_concepts
-}  // namespace mp
diff --git a/src/include/units/bits/tools.h b/src/include/units/bits/tools.h
index 56524e53..42c781c3 100644
--- a/src/include/units/bits/tools.h
+++ b/src/include/units/bits/tools.h
@@ -22,7 +22,7 @@
 
 #pragma once
 
-#include "stdconcepts.h"
+#include <experimental/ranges/concepts>
 #include <ratio>
 #include <type_traits>
 
@@ -38,8 +38,6 @@ namespace std {
 
 namespace units {
 
-  using namespace mp::std_concepts;  // todo Remove when std::concepts will arrive
-
   template<typename T>
   concept bool Number = requires(T a, T b) {
     { a + b } -> T;
diff --git a/src/include/units/dimension.h b/src/include/units/dimension.h
index 5f4d5e54..827eb39f 100644
--- a/src/include/units/dimension.h
+++ b/src/include/units/dimension.h
@@ -102,7 +102,7 @@ namespace units {
   concept bool Dimension =
       std::is_empty_v<T> &&
       detail::is_dimension<typename T::base_type> &&
-      DerivedFrom<T, typename T::base_type>;
+      std::experimental::ranges::DerivedFrom<T, typename T::base_type>;
 
 
   // dim_invert
diff --git a/src/include/units/quantity.h b/src/include/units/quantity.h
index 0280fff1..bc4e018f 100644
--- a/src/include/units/quantity.h
+++ b/src/include/units/quantity.h
@@ -30,7 +30,7 @@ namespace units {
   // is_quantity
 
   template<Dimension D, Unit U, Number Rep>
-      requires Same<D, typename U::dimension>
+      requires std::experimental::ranges::Same<D, typename U::dimension>
   class quantity;
 
   namespace detail {
@@ -95,7 +95,7 @@ namespace units {
   }  // namespace detail
 
   template<Quantity To, Dimension D, Unit U, Number Rep>
-      requires Same<typename To::dimension, D> constexpr
+      requires std::experimental::ranges::Same<typename To::dimension, D> constexpr
   To quantity_cast(const quantity<D, U, Rep>& q)
   {
     using c_ratio = std::ratio_divide<typename U::ratio, typename To::unit::ratio>;
@@ -116,7 +116,7 @@ namespace units {
   // quantity
 
   template<Dimension D, Unit U, Number Rep>
-      requires Same<D, typename U::dimension>
+      requires std::experimental::ranges::Same<D, typename U::dimension>
   class quantity {
     Rep value_;
 
@@ -130,17 +130,18 @@ namespace units {
     quantity() = default;
     quantity(const quantity&) = default;
 
-    template<ConvertibleTo<rep> Rep2>
+    template<std::experimental::ranges::ConvertibleTo<rep> Rep2>
         requires treat_as_floating_point<rep> || (!treat_as_floating_point<Rep2>)
     constexpr explicit quantity(const Rep2& r) : value_{static_cast<rep>(r)}
     {
     }
 
     template<Quantity Q2>
-        requires Same<dimension, typename Q2::dimension> && ConvertibleTo<typename Q2::rep, rep> &&
-        (treat_as_floating_point<rep> ||
-         (std::ratio_divide<typename Q2::unit::ratio, typename unit::ratio>::den == 1 &&
-          !treat_as_floating_point<typename Q2::rep>))
+        requires std::experimental::ranges::Same<dimension, typename Q2::dimension> &&
+                 std::experimental::ranges::ConvertibleTo<typename Q2::rep, rep> &&
+                 (treat_as_floating_point<rep> ||
+                   (std::ratio_divide<typename Q2::unit::ratio, typename unit::ratio>::den == 1 &&
+                   !treat_as_floating_point<typename Q2::rep>))
     constexpr quantity(const Q2& q) : value_{quantity_cast<quantity>(q).count()}
     {
     }
diff --git a/src/include/units/si/frequency.h b/src/include/units/si/frequency.h
index 20685f57..433f905f 100644
--- a/src/include/units/si/frequency.h
+++ b/src/include/units/si/frequency.h
@@ -52,7 +52,7 @@ namespace units {
   using frequency = quantity<dimension_frequency, U, Rep>;
 
   template<typename T>
-  concept bool Frequency =  Quantity<T> && Same<typename T::dimension, dimension_frequency>;
+  concept bool Frequency =  Quantity<T> && std::experimental::ranges::Same<typename T::dimension, dimension_frequency>;
 
   // ...
 
diff --git a/src/include/units/si/length.h b/src/include/units/si/length.h
index 10d2d90a..e879253a 100644
--- a/src/include/units/si/length.h
+++ b/src/include/units/si/length.h
@@ -46,7 +46,7 @@ namespace units {
   using length = quantity<dimension_length, U, Rep>;
 
   template<typename T>
-  concept bool Length = Quantity<T> && Same<typename T::dimension, dimension_length>;
+  concept bool Length = Quantity<T> && std::experimental::ranges::Same<typename T::dimension, dimension_length>;
 
   namespace literals {
 
diff --git a/src/include/units/si/time.h b/src/include/units/si/time.h
index ee8ce0cb..29605c05 100644
--- a/src/include/units/si/time.h
+++ b/src/include/units/si/time.h
@@ -53,7 +53,7 @@ namespace units {
 
 
   template<typename T>
-  concept bool Time = Quantity<T> && Same<typename T::dimension, dimension_time>;
+  concept bool Time = Quantity<T> && std::experimental::ranges::Same<typename T::dimension, dimension_time>;
 
   // ...
 
diff --git a/src/include/units/si/velocity.h b/src/include/units/si/velocity.h
index 08ccd21a..579b1c5a 100644
--- a/src/include/units/si/velocity.h
+++ b/src/include/units/si/velocity.h
@@ -44,7 +44,7 @@ namespace units {
   using velocity = quantity<dimension_velocity, U, Rep>;
 
   template<typename T>
-  concept bool Velocity = Quantity<T> && Same<typename T::dimension, dimension_velocity>;
+  concept bool Velocity = Quantity<T> && std::experimental::ranges::Same<typename T::dimension, dimension_velocity>;
 
   // ...
 
diff --git a/src/include/units/unit.h b/src/include/units/unit.h
index 42e338b0..965ae609 100644
--- a/src/include/units/unit.h
+++ b/src/include/units/unit.h
@@ -50,6 +50,6 @@ namespace units {
   concept bool Unit =
       std::is_empty_v<T> &&
       detail::is_unit<typename T::base_type> &&
-      DerivedFrom<T, typename T::base_type>;
+      std::experimental::ranges::DerivedFrom<T, typename T::base_type>;
 
 }  // namespace units