libstdc++-v3/include/experimental/numeric

   1 // <experimental/numeric> -*- C++ -*-
   2
   3 // Copyright (C) 2015-2021 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // Under Section 7 of GPL version 3, you are granted additional
  17 // permissions described in the GCC Runtime Library Exception, version
  18 // 3.1, as published by the Free Software Foundation.
  19
  20 // You should have received a copy of the GNU General Public License and
  21 // a copy of the GCC Runtime Library Exception along with this program;
  22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 // <http://www.gnu.org/licenses/>.
  24
  25 /** @file experimental/numeric
  26  *  This is a TS C++ Library header.
  27  *  @ingroup libfund-ts
  28  */
  29
  30 //
  31 // N4336 Working Draft, C++ Extensions for Library Fundamentals, Version 2
  32 //
  33
  34 #ifndef _GLIBCXX_EXPERIMENTAL_NUMERIC
  35 #define _GLIBCXX_EXPERIMENTAL_NUMERIC 1
  36
  37 #pragma GCC system_header
  38
  39 #if __cplusplus >= 201402L
  40
  41 #include <numeric>
  42 #include <experimental/type_traits>
  43
  44 namespace std _GLIBCXX_VISIBILITY(default)
  45 {
  46 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  47
  48 namespace experimental
  49 {
  50 inline namespace fundamentals_v2
  51 {
  52 #define __cpp_lib_experimental_gcd_lcm 201411
  53
  54   /// Greatest common divisor
  55   template<typename _Mn, typename _Nn>
  56     constexpr common_type_t<_Mn, _Nn>
  57     gcd(_Mn __m, _Nn __n) noexcept
  58     {
  59       static_assert(is_integral_v<_Mn>,
  60           "std::experimental::gcd arguments must be integers");
  61       static_assert(is_integral_v<_Nn>,
  62           "std::experimental::gcd arguments must be integers");
  63       static_assert(_Mn(2) != _Mn(1),
  64           "std::experimental::gcd arguments must not be bool");
  65       static_assert(_Nn(2) != _Nn(1),
  66           "std::experimental::gcd arguments must not be bool");
  67       using _Up = make_unsigned_t<common_type_t<_Mn, _Nn>>;
  68       return std::__detail::__gcd(std::__detail::__absu<_Up>(__m),
  69                                   std::__detail::__absu<_Up>(__n));
  70     }
  71
  72   /// Least common multiple
  73   template<typename _Mn, typename _Nn>
  74     constexpr common_type_t<_Mn, _Nn>
  75     lcm(_Mn __m, _Nn __n)
  76     {
  77       static_assert(is_integral_v<_Mn>,
  78           "std::experimental::lcm arguments must be integers");
  79       static_assert(is_integral_v<_Nn>,
  80           "std::experimental::lcm arguments must be integers");
  81       static_assert(_Mn(2) != _Mn(1),
  82           "std::experimental::lcm arguments must not be bool");
  83       static_assert(_Nn(2) != _Nn(1),
  84           "std::experimental::lcm arguments must not be bool");
  85       using _Up = make_unsigned_t<common_type_t<_Mn, _Nn>>;
  86       return std::__detail::__lcm(std::__detail::__absu<_Up>(__m),
  87                                   std::__detail::__absu<_Up>(__n));
  88     }
  89 } // namespace fundamentals_v2
  90 } // namespace experimental
  91
  92 _GLIBCXX_END_NAMESPACE_VERSION
  93 } // namespace std
  94
  95 #endif // __cplusplus <= 201103L
  96
  97 #endif // _GLIBCXX_EXPERIMENTAL_NUMERIC