xref: /llvm-project/libcxx/test/std/utilities/expected/expected.void/ctor/ctor.default.pass.cpp (revision 6a54dfbfe534276d644d7f9c027f0deeb748dd53)
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, c++20
10 
11 // constexpr expected() noexcept;
12 
13 #include <cassert>
14 #include <expected>
15 #include <type_traits>
16 
17 #include "test_macros.h"
18 
19 // Test noexcept
20 
21 struct NoDefaultCtor {
22   constexpr NoDefaultCtor() = delete;
23 };
24 
25 static_assert(std::is_nothrow_default_constructible_v<std::expected<void, int>>);
26 static_assert(std::is_nothrow_default_constructible_v<std::expected<void, NoDefaultCtor>>);
27 
28 struct MyInt {
29   int i;
30   friend constexpr bool operator==(const MyInt&, const MyInt&) = default;
31 };
32 
33 constexpr bool test() {
34   // default constructible
35   {
36     std::expected<void, int> e;
37     assert(e.has_value());
38   }
39 
40   // non-default constructible
41   {
42     std::expected<void, NoDefaultCtor> e;
43     assert(e.has_value());
44   }
45 
46   return true;
47 }
48 
49 int main(int, char**) {
50   test();
51   static_assert(test());
52   return 0;
53 }
54