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// UNSUPPORTED: c++03, c++11, c++14, c++17
10
11// <optional>
12
13// [optional.nullops], comparison with nullopt
14
15// template<class T>
16// constexpr strong_ordering operator<=>(const optional<T>&, nullopt_t) noexcept;
17
18#include <cassert>
19#include <compare>
20#include <optional>
21
22#include "test_comparisons.h"
23
24constexpr bool test() {
25 {
26 std::optional<int> op;
27 assert((std::nullopt <=> op) == std::strong_ordering::equal);
28 assert(testOrder(std::nullopt, op, std::strong_ordering::equal));
29 assert((op <=> std::nullopt) == std::strong_ordering::equal);
30 assert(testOrder(op, std::nullopt, std::strong_ordering::equal));
31 }
32 {
33 std::optional<int> op{1};
34 assert((std::nullopt <=> op) == std::strong_ordering::less);
35 assert(testOrder(std::nullopt, op, std::strong_ordering::less));
36 }
37 {
38 std::optional<int> op{1};
39 assert((op <=> std::nullopt) == std::strong_ordering::greater);
40 assert(testOrder(op, std::nullopt, std::strong_ordering::greater));
41 }
42
43 return true;
44}
45
46int main(int, char**) {
47 assert(test());
48 static_assert(test());
49 return 0;
50}
51

source code of libcxx/test/std/utilities/optional/optional.nullops/compare.three_way.pass.cpp