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 // time_point 12 13 // time_point& operator-=(const duration& d); 14 // constexpr in c++17 15 16 #include <chrono> 17 #include <cassert> 18 19 #include "test_macros.h" 20 21 #if TEST_STD_VER > 14 constexpr_test()22constexpr bool constexpr_test() 23 { 24 typedef std::chrono::system_clock Clock; 25 typedef std::chrono::milliseconds Duration; 26 std::chrono::time_point<Clock, Duration> t(Duration(5)); 27 t -= Duration(4); 28 return t.time_since_epoch() == Duration(1); 29 } 30 #endif 31 main(int,char **)32int main(int, char**) 33 { 34 { 35 typedef std::chrono::system_clock Clock; 36 typedef std::chrono::milliseconds Duration; 37 std::chrono::time_point<Clock, Duration> t(Duration(3)); 38 t -= Duration(2); 39 assert(t.time_since_epoch() == Duration(1)); 40 } 41 42 #if TEST_STD_VER > 14 43 static_assert(constexpr_test(), ""); 44 #endif 45 46 return 0; 47 } 48