libcxx/test/std/time/time.duration/time.duration.arithmetic/op_--.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // <chrono>
  10
  11 // duration
  12
  13 // constexpr duration& operator--();  // constexpr in C++17
  14
  15 #include <chrono>
  16 #include <cassert>
  17
  18 #include "test_macros.h"
  19
  20 #if TEST_STD_VER > 14
  21 constexpr bool test_constexpr()
  22 {
  23     std::chrono::hours h(3);
  24     return (--h).count() == 2;
  25 }
  26 #endif
  27
  28 int main(int, char**)
  29 {
  30     {
  31     std::chrono::hours h(3);
  32     std::chrono::hours& href = --h;
  33     assert(&href == &h);
  34     assert(h.count() == 2);
  35     }
  36
  37 #if TEST_STD_VER > 14
  38     static_assert(test_constexpr(), "");
  39 #endif
  40
  41   return 0;
  42 }