feat: std::numeric_limits support added

Resolves #408

src/core/CMakeLists.txt

@@ -78,6 +78,7 @@ add_mp_units_module(
             include/mp-units/concepts.h
             include/mp-units/core.h
             include/mp-units/framework.h
+            include/mp-units/limits.h
     MODULE_INTERFACE_UNIT mp-units-core.cpp
 )
 

src/core/include/mp-units/core.h

@@ -26,6 +26,7 @@
 #include <mp-units/compat_macros.h>
 #include <mp-units/concepts.h>
 #include <mp-units/framework.h>
+#include <mp-units/limits.h>
 
 #if MP_UNITS_HOSTED
 #include <mp-units/cartesian_vector.h>

src/core/include/mp-units/limits.h

@@ -0,0 +1,154 @@
+// 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 <mp-units/bits/module_macros.h>
+#include <mp-units/framework/quantity.h>
+#include <mp-units/framework/quantity_point.h>
+
+#ifndef MP_UNITS_IN_MODULE_INTERFACE
+#ifdef MP_UNITS_IMPORT_STD
+import std;
+#else
+#include <limits>
+#endif  // MP_UNITS_IMPORT_STD
+#endif  // MP_UNITS_IN_MODULE_INTERFACE
+
+template<auto R, typename Rep>
+  requires requires { typename std::numeric_limits<Rep>; }
+class std::numeric_limits<mp_units::quantity<R, Rep>> : public std::numeric_limits<Rep> {
+public:
+  static constexpr mp_units::quantity<R, Rep> min() noexcept
+    requires requires { mp_units::quantity<R, Rep>::min(); }
+  {
+    return mp_units::quantity<R, Rep>::min();
+  }
+
+  static constexpr mp_units::quantity<R, Rep> max() noexcept
+    requires requires { mp_units::quantity<R, Rep>::max(); }
+  {
+    return mp_units::quantity<R, Rep>::max();
+  }
+
+  static constexpr mp_units::quantity<R, Rep> lowest() noexcept
+    requires requires { std::numeric_limits<Rep>::lowest(); }
+  {
+    return {std::numeric_limits<Rep>::lowest(), R};
+  }
+
+  static constexpr mp_units::quantity<R, Rep> epsilon() noexcept
+    requires requires { std::numeric_limits<Rep>::epsilon(); }
+  {
+    return {std::numeric_limits<Rep>::epsilon(), R};
+  }
+
+  static constexpr mp_units::quantity<R, Rep> round_error() noexcept
+    requires requires { std::numeric_limits<Rep>::round_error(); }
+  {
+    return {std::numeric_limits<Rep>::round_error(), R};
+  }
+
+  static constexpr mp_units::quantity<R, Rep> infinity() noexcept
+    requires requires { std::numeric_limits<Rep>::infinity(); }
+  {
+    return {std::numeric_limits<Rep>::infinity(), R};
+  }
+
+  static constexpr mp_units::quantity<R, Rep> quiet_NaN() noexcept
+    requires requires { std::numeric_limits<Rep>::quiet_NaN(); }
+  {
+    return {std::numeric_limits<Rep>::quiet_NaN(), R};
+  }
+
+  static constexpr mp_units::quantity<R, Rep> signaling_NaN() noexcept
+    requires requires { std::numeric_limits<Rep>::signaling_NaN(); }
+  {
+    return {std::numeric_limits<Rep>::signaling_NaN(), R};
+  }
+
+  static constexpr mp_units::quantity<R, Rep> denorm_min() noexcept
+    requires requires { std::numeric_limits<Rep>::denorm_min(); }
+  {
+    return {std::numeric_limits<Rep>::denorm_min(), R};
+  }
+};
+
+
+template<auto R, auto PO, typename Rep>
+  requires requires { typename std::numeric_limits<Rep>; }
+class std::numeric_limits<mp_units::quantity_point<R, PO, Rep>> : public std::numeric_limits<Rep> {
+public:
+  static constexpr mp_units::quantity_point<R, PO, Rep> min() noexcept
+    requires requires { mp_units::quantity_point<R, PO, Rep>::min(); }
+  {
+    return mp_units::quantity_point<R, PO, Rep>::min();
+  }
+
+  static constexpr mp_units::quantity_point<R, PO, Rep> max() noexcept
+    requires requires { mp_units::quantity_point<R, PO, Rep>::max(); }
+  {
+    return mp_units::quantity_point<R, PO, Rep>::max();
+  }
+
+  static constexpr mp_units::quantity_point<R, PO, Rep> lowest() noexcept
+    requires requires { std::numeric_limits<mp_units::quantity<R, Rep>>::lowest(); }
+  {
+    return {std::numeric_limits<mp_units::quantity<R, Rep>>::lowest(), PO};
+  }
+
+  static constexpr mp_units::quantity_point<R, PO, Rep> epsilon() noexcept
+    requires requires { std::numeric_limits<mp_units::quantity<R, Rep>>::epsilon(); }
+  {
+    return {std::numeric_limits<mp_units::quantity<R, Rep>>::epsilon(), PO};
+  }
+
+  static constexpr mp_units::quantity_point<R, PO, Rep> round_error() noexcept
+    requires requires { std::numeric_limits<mp_units::quantity<R, Rep>>::round_error(); }
+  {
+    return {std::numeric_limits<mp_units::quantity<R, Rep>>::round_error(), PO};
+  }
+
+  static constexpr mp_units::quantity_point<R, PO, Rep> infinity() noexcept
+    requires requires { std::numeric_limits<mp_units::quantity<R, Rep>>::infinity(); }
+  {
+    return {std::numeric_limits<mp_units::quantity<R, Rep>>::infinity(), PO};
+  }
+
+  static constexpr mp_units::quantity_point<R, PO, Rep> quiet_NaN() noexcept
+    requires requires { std::numeric_limits<mp_units::quantity<R, Rep>>::quiet_NaN(); }
+  {
+    return {std::numeric_limits<mp_units::quantity<R, Rep>>::quiet_NaN(), PO};
+  }
+
+  static constexpr mp_units::quantity_point<R, PO, Rep> signaling_NaN() noexcept
+    requires requires { std::numeric_limits<mp_units::quantity<R, Rep>>::signaling_NaN(); }
+  {
+    return {std::numeric_limits<mp_units::quantity<R, Rep>>::signaling_NaN(), PO};
+  }
+
+  static constexpr mp_units::quantity_point<R, PO, Rep> denorm_min() noexcept
+    requires requires { std::numeric_limits<mp_units::quantity<R, Rep>>::denorm_min(); }
+  {
+    return {std::numeric_limits<mp_units::quantity<R, Rep>>::denorm_min(), PO};
+  }
+};

src/core/include/mp-units/math.h

@@ -320,7 +320,8 @@ template<auto R1, typename Rep1, auto R2, typename Rep2>
  */
 template<Representation Rep, Reference R>
   requires requires { std::numeric_limits<Rep>::epsilon(); }
-[[nodiscard]] constexpr quantity<R{}, Rep> epsilon(R r) noexcept
+[[deprecated("Use `std::numeric_limits<Quantity>::epsilon()` instead")]] [[nodiscard]] constexpr quantity<R{}, Rep>
+epsilon(R r) noexcept
 {
   return {static_cast<Rep>(std::numeric_limits<Rep>::epsilon()), r};
 }