1//===----------------------------------------------------------------------===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8 9#ifndef _LIBCPP___UTILITY_SWAP_H 10#define _LIBCPP___UTILITY_SWAP_H 11 12#include <__config> 13#include <__type_traits/is_move_assignable.h> 14#include <__type_traits/is_move_constructible.h> 15#include <__type_traits/is_nothrow_move_assignable.h> 16#include <__type_traits/is_nothrow_move_constructible.h> 17#include <__type_traits/is_swappable.h> 18#include <__utility/declval.h> 19#include <__utility/move.h> 20#include <cstddef> 21 22#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 23# pragma GCC system_header 24#endif 25 26_LIBCPP_BEGIN_NAMESPACE_STD 27 28#ifndef _LIBCPP_CXX03_LANG 29template <class _Tp> 30using __swap_result_t = typename enable_if<is_move_constructible<_Tp>::value && is_move_assignable<_Tp>::value>::type; 31#else 32template <class> 33using __swap_result_t = void; 34#endif 35 36template <class _Tp> 37inline _LIBCPP_INLINE_VISIBILITY __swap_result_t<_Tp> _LIBCPP_CONSTEXPR_SINCE_CXX20 swap(_Tp& __x, _Tp& __y) 38 _NOEXCEPT_(is_nothrow_move_constructible<_Tp>::value&& is_nothrow_move_assignable<_Tp>::value) { 39 _Tp __t(_VSTD::move(__x)); 40 __x = _VSTD::move(__y); 41 __y = _VSTD::move(__t); 42} 43 44template <class _Tp, size_t _Np> 45inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 typename enable_if<__is_swappable<_Tp>::value>::type 46swap(_Tp (&__a)[_Np], _Tp (&__b)[_Np]) _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) { 47 for (size_t __i = 0; __i != _Np; ++__i) { 48 swap(__a[__i], __b[__i]); 49 } 50} 51 52_LIBCPP_END_NAMESPACE_STD 53 54#endif // _LIBCPP___UTILITY_SWAP_H 55