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// -*- 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;
}
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