| // { dg-do run { target c++17 } } |
| |
| // Copyright (C) 2013-2023 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 3, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License along |
| // with this library; see the file COPYING3. If not see |
| // <http://www.gnu.org/licenses/>. |
| |
| #include <optional> |
| #include <testsuite_hooks.h> |
| |
| int main() |
| { |
| // [20.5.6] Disengaged state indicator |
| static_assert( std::is_same<decltype(std::nullopt), const std::nullopt_t>(), "" ); |
| static_assert( std::is_empty<std::nullopt_t>(), "" ); |
| static_assert( __is_literal_type(std::nullopt_t), "" ); |
| static_assert( !std::is_default_constructible<std::nullopt_t>(), "" ); |
| |
| { |
| std::optional<int> o = std::nullopt; |
| VERIFY( !o ); |
| } |
| |
| { |
| std::optional<int> o = { std::nullopt }; |
| VERIFY( !o ); |
| } |
| |
| { |
| std::optional<int> o { std::nullopt }; |
| VERIFY( !o ); |
| } |
| } |