| // -*- 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 std::add_lvalue_reference_t<element_type> operator*() const; |
| // constexpr element_type* operator->() const noexcept; |
| |
| #include <experimental/memory> |
| #include <type_traits> |
| #include <cassert> |
| |
| template <class T, class Object = T> |
| constexpr void test_deref() { |
| using Ptr = std::experimental::observer_ptr<T>; |
| Object obj; |
| |
| { |
| Ptr const ptr(&obj); |
| T& r = *ptr; |
| assert(&r == &obj); |
| } |
| { |
| Ptr const ptr(&obj); |
| T* r = ptr.operator->(); |
| assert(r == &obj); |
| static_assert(noexcept(ptr.operator->())); |
| } |
| } |
| |
| struct Bar {}; |
| struct Foo { |
| int member = 42; |
| }; |
| |
| constexpr bool test() { |
| test_deref<Bar>(); |
| test_deref<int>(); |
| |
| { |
| Foo foo; |
| std::experimental::observer_ptr<Foo> ptr(&foo); |
| assert(&ptr->member == &foo.member); |
| } |
| |
| return true; |
| } |
| |
| int main(int, char**) { |
| test(); |
| static_assert(test()); |
| |
| return 0; |
| } |