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// Copyright (C) 2019-2023 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// { dg-options "-std=gnu++2a" }
// { dg-do run { target c++2a } }
#include <memory>
#include <testsuite_hooks.h>
template<typename T, typename... Args>
concept can_construct_at = requires(T* p, Args&&... args)
{
p = std::construct_at(p, std::forward<Args>(args)...);
};
static_assert( can_construct_at<int> );
static_assert( can_construct_at<int, int> );
static_assert( !can_construct_at<int, int, int> );
// Not required by C++20:
static_assert( noexcept(std::construct_at(std::declval<int*>(), 1)) );
void
test01()
{
int i = -1;
auto p = std::construct_at(&i);
VERIFY( p == &i );
VERIFY( i == 0 );
p = std::construct_at(&i, 42);
VERIFY( p == &i );
VERIFY( i == 42 );
}
struct X {
X(char&, void*) { }
};
static_assert( can_construct_at<X, char&, void*> );
static_assert( !can_construct_at<X> );
static_assert( !can_construct_at<X, char> );
static_assert( !can_construct_at<X, char&, const void*> );
static_assert( !noexcept(std::construct_at(std::declval<X*>(), std::declval<char&>(), std::declval<void*>())) );
int
main()
{
test01();
}
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