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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 void swap(observer_ptr& other) noexcept;
//
// template <class W>
// void swap(observer_ptr<W>& lhs, observer_ptr<W>& rhs) noexcept;
#include <experimental/memory>
#include <type_traits>
#include <cassert>
template <class T, class Object = T>
constexpr void test_swap() {
using Ptr = std::experimental::observer_ptr<T>;
Object obj1, obj2;
{
Ptr ptr1(&obj1);
Ptr ptr2(&obj2);
assert(ptr1.get() == &obj1);
assert(ptr2.get() == &obj2);
ptr1.swap(ptr2);
assert(ptr1.get() == &obj2);
assert(ptr2.get() == &obj1);
static_assert(noexcept(ptr1.swap(ptr2)));
static_assert(std::is_same<decltype(ptr1.swap(ptr2)), void>::value);
}
{
Ptr ptr1(&obj1);
Ptr ptr2(&obj2);
assert(ptr1.get() == &obj1);
assert(ptr2.get() == &obj2);
std::experimental::swap(ptr1, ptr2);
assert(ptr1.get() == &obj2);
assert(ptr2.get() == &obj1);
static_assert(noexcept(std::experimental::swap(ptr1, ptr2)));
static_assert(std::is_same<decltype(std::experimental::swap(ptr1, ptr2)), void>::value);
}
}
struct Bar {};
constexpr bool test() {
test_swap<Bar>();
test_swap<int>();
test_swap<void, int>();
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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