7a62bee611
This patch adds std::experimental::observer_ptr (n4282) and also fixes LWG2516. Co-Authored-By: Louis Dionne <ldionne.2@gmail.com> Differential Revision: https://reviews.llvm.org/D63230
62 lines
1.4 KiB
C++
62 lines
1.4 KiB
C++
// -*- 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 reset(element_type* p = nullptr) noexcept;
|
|
|
|
#include <experimental/memory>
|
|
#include <type_traits>
|
|
#include <cassert>
|
|
|
|
template <class T, class Object = T>
|
|
constexpr void test_reset() {
|
|
using Ptr = std::experimental::observer_ptr<T>;
|
|
Object obj1, obj2;
|
|
|
|
{
|
|
Ptr ptr(&obj1);
|
|
assert(ptr.get() == &obj1);
|
|
ptr.reset(&obj2);
|
|
assert(ptr.get() == &obj2);
|
|
static_assert(noexcept(ptr.reset(&obj2)));
|
|
static_assert(std::is_same<decltype(ptr.reset(&obj2)), void>::value);
|
|
}
|
|
{
|
|
Ptr ptr(&obj1);
|
|
assert(ptr.get() == &obj1);
|
|
ptr.reset();
|
|
assert(ptr.get() == nullptr);
|
|
static_assert(noexcept(ptr.reset()));
|
|
static_assert(std::is_same<decltype(ptr.reset()), void>::value);
|
|
}
|
|
}
|
|
|
|
struct Bar {};
|
|
|
|
constexpr bool test() {
|
|
test_reset<Bar>();
|
|
test_reset<int>();
|
|
test_reset<void, int>();
|
|
|
|
return true;
|
|
}
|
|
|
|
int main(int, char**) {
|
|
test();
|
|
static_assert(test());
|
|
|
|
return 0;
|
|
}
|