blob: d9b3c151755fad570e9174fb3e033e7f4232dcdb (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___UTILITY_EXCHANGE_H
#define _LIBCPP___UTILITY_EXCHANGE_H
#include <__config>
#include <__utility/forward.h>
#include <__utility/move.h>
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER > 11
template<class _T1, class _T2 = _T1>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
_T1 exchange(_T1& __obj, _T2&& __new_value)
noexcept(is_nothrow_move_constructible<_T1>::value && is_nothrow_assignable<_T1&, _T2>::value)
{
_T1 __old_value = _VSTD::move(__obj);
__obj = _VSTD::forward<_T2>(__new_value);
return __old_value;
}
#endif // _LIBCPP_STD_VER > 11
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___UTILITY_EXCHANGE_H
|
