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// UNSUPPORTED: c++03, c++11, c++14, c++17
9
10// <chrono>
11// class year;
12
13// constexpr year operator-(const year& x, const years& y) noexcept;
14// Returns: x + -y.
15//
16// constexpr years operator-(const year& x, const year& y) noexcept;
17// Returns: If x.ok() == true and y.ok() == true, returns a value m in the range
18// [years{0}, years{11}] satisfying y + m == x.
19// Otherwise the value returned is unspecified.
20// [Example: January - February == years{11}. -end example]
21
22#include <chrono>
23#include <cassert>
24#include <type_traits>
25#include <utility>
26
27#include "test_macros.h"
28
29using year = std::chrono::year;
30using years = std::chrono::years;
31
32constexpr bool test() {
33 year y{1223};
34 for (int i = 1100; i <= 1110; ++i) {
35 year y1 = y - years{i};
36 years ys1 = y - year{i};
37 assert(static_cast<int>(y1) == 1223 - i);
38 assert(ys1.count() == 1223 - i);
39 }
40
41 return true;
42}
43
44int main(int, char**) {
45 ASSERT_NOEXCEPT(std::declval<year>() - std::declval<years>());
46 ASSERT_SAME_TYPE(year, decltype(std::declval<year>() - std::declval<years>()));
47
48 ASSERT_NOEXCEPT(std::declval<year>() - std::declval<year>());
49 ASSERT_SAME_TYPE(years, decltype(std::declval<year>() - std::declval<year>()));
50
51 test();
52 static_assert(test());
53
54 return 0;
55}
56

source code of libcxx/test/std/time/time.cal/time.cal.year/time.cal.year.nonmembers/minus.pass.cpp