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 |
10 | // <optional> |
11 | |
12 | // struct nullopt_t{see below}; |
13 | // inline constexpr nullopt_t nullopt(unspecified); |
14 | |
15 | // [optional.nullopt]/2: |
16 | // Type nullopt_t shall not have a default constructor or an initializer-list |
17 | // constructor, and shall not be an aggregate. |
18 | |
19 | #include <optional> |
20 | #include <type_traits> |
21 | |
22 | #include "test_macros.h" |
23 | |
24 | using std::nullopt_t; |
25 | using std::nullopt; |
26 | |
27 | constexpr bool test() |
28 | { |
29 | nullopt_t foo{nullopt}; |
30 | (void)foo; |
31 | return true; |
32 | } |
33 | |
34 | int main(int, char**) |
35 | { |
36 | static_assert(std::is_empty_v<nullopt_t>); |
37 | static_assert(!std::is_default_constructible_v<nullopt_t>); |
38 | |
39 | static_assert(std::is_same_v<const nullopt_t, decltype(nullopt)>); |
40 | static_assert(test()); |
41 | |
42 | return 0; |
43 | } |
44 | |