| // -*- C++ -*- |
| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // UNSUPPORTED: c++03, c++11, c++14 |
| // REQUIRES: c++experimental |
| |
| // <experimental/memory> |
| |
| // observer_ptr |
| // |
| // constexpr explicit operator bool() const noexcept; |
| |
| #include <experimental/memory> |
| #include <type_traits> |
| #include <cassert> |
| |
| template <class T, class Object = T> |
| constexpr void test_operator_bool() { |
| using Ptr = std::experimental::observer_ptr<T>; |
| Object obj; |
| |
| { |
| Ptr const ptr(&obj); |
| bool b = static_cast<bool>(ptr); |
| assert(b); |
| |
| static_assert(noexcept(static_cast<bool>(ptr))); |
| } |
| |
| { |
| Ptr const ptr(nullptr); |
| bool b = static_cast<bool>(ptr); |
| assert(!b); |
| } |
| |
| static_assert(!std::is_convertible<Ptr const, bool>::value); |
| static_assert(std::is_constructible<bool, Ptr const>::value); |
| } |
| |
| struct Bar {}; |
| |
| constexpr bool test() { |
| test_operator_bool<Bar>(); |
| test_operator_bool<int>(); |
| test_operator_bool<void, int>(); |
| |
| return true; |
| } |
| |
| int main(int, char**) { |
| test(); |
| static_assert(test()); |
| |
| return 0; |
| } |