libstdc++-v3/testsuite/std/time/year_month/2.cc

   1 // { dg-options "-std=gnu++2a" }
   2 // { dg-do compile { target c++2a } }
   3
   4 // Copyright (C) 2020-2021 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 // Class template year_month [time.cal.year_month]
  22
  23 #include <chrono>
  24
  25 constexpr void
  26 constexpr_year_month_op_overload_disambiguation()
  27 {
  28   using namespace std::chrono;
  29   using decades = duration<long long, std::ratio<31556952 * 10>>;
  30   static_assert(std::convertible_to<decades, months>
  31                 && std::convertible_to<decades, years>);
  32   using ym = year_month;
  33
  34   constexpr ym ym1 = 2015y/June;
  35   static_assert(ym1 + decades{1} == 2025y/June);
  36   static_assert(ym1 - decades{1} == 2005y/June);
  37   static_assert(decades{1} + ym1 == 2025y/June);
  38   static_assert((ym{ym1} += decades{1}) == 2025y/June);
  39   static_assert((ym{ym1} -= decades{1}) == 2005y/June);
  40 }