xref: /openbsd-src/gnu/llvm/libcxx/include/__utility/swap.h (revision 4bdff4bed0e3d54e55670334c7d0077db4170f86)
176d0caaeSpatrick //===----------------------------------------------------------------------===//
276d0caaeSpatrick //
376d0caaeSpatrick // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
476d0caaeSpatrick // See https://llvm.org/LICENSE.txt for license information.
576d0caaeSpatrick // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
676d0caaeSpatrick //
776d0caaeSpatrick //===----------------------------------------------------------------------===//
876d0caaeSpatrick 
976d0caaeSpatrick #ifndef _LIBCPP___UTILITY_SWAP_H
1076d0caaeSpatrick #define _LIBCPP___UTILITY_SWAP_H
1176d0caaeSpatrick 
1276d0caaeSpatrick #include <__config>
13*4bdff4beSrobert #include <__type_traits/is_move_assignable.h>
14*4bdff4beSrobert #include <__type_traits/is_move_constructible.h>
15*4bdff4beSrobert #include <__type_traits/is_nothrow_move_assignable.h>
16*4bdff4beSrobert #include <__type_traits/is_nothrow_move_constructible.h>
17*4bdff4beSrobert #include <__type_traits/is_swappable.h>
1876d0caaeSpatrick #include <__utility/declval.h>
1976d0caaeSpatrick #include <__utility/move.h>
2076d0caaeSpatrick #include <cstddef>
2176d0caaeSpatrick 
2276d0caaeSpatrick #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
2376d0caaeSpatrick #  pragma GCC system_header
2476d0caaeSpatrick #endif
2576d0caaeSpatrick 
2676d0caaeSpatrick _LIBCPP_BEGIN_NAMESPACE_STD
2776d0caaeSpatrick 
2876d0caaeSpatrick #ifndef _LIBCPP_CXX03_LANG
2976d0caaeSpatrick template <class _Tp>
3076d0caaeSpatrick using __swap_result_t = typename enable_if<is_move_constructible<_Tp>::value && is_move_assignable<_Tp>::value>::type;
3176d0caaeSpatrick #else
3276d0caaeSpatrick template <class>
3376d0caaeSpatrick using __swap_result_t = void;
3476d0caaeSpatrick #endif
3576d0caaeSpatrick 
3676d0caaeSpatrick template <class _Tp>
swap(_Tp & __x,_Tp & __y)37*4bdff4beSrobert inline _LIBCPP_INLINE_VISIBILITY __swap_result_t<_Tp> _LIBCPP_CONSTEXPR_SINCE_CXX20 swap(_Tp& __x, _Tp& __y)
3876d0caaeSpatrick     _NOEXCEPT_(is_nothrow_move_constructible<_Tp>::value&& is_nothrow_move_assignable<_Tp>::value) {
3976d0caaeSpatrick   _Tp __t(_VSTD::move(__x));
4076d0caaeSpatrick   __x = _VSTD::move(__y);
4176d0caaeSpatrick   __y = _VSTD::move(__t);
4276d0caaeSpatrick }
4376d0caaeSpatrick 
4476d0caaeSpatrick template <class _Tp, size_t _Np>
45*4bdff4beSrobert inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 typename enable_if<__is_swappable<_Tp>::value>::type
swap(_Tp (& __a)[_Np],_Tp (& __b)[_Np])4676d0caaeSpatrick swap(_Tp (&__a)[_Np], _Tp (&__b)[_Np]) _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) {
4776d0caaeSpatrick   for (size_t __i = 0; __i != _Np; ++__i) {
4876d0caaeSpatrick     swap(__a[__i], __b[__i]);
4976d0caaeSpatrick   }
5076d0caaeSpatrick }
5176d0caaeSpatrick 
5276d0caaeSpatrick _LIBCPP_END_NAMESPACE_STD
5376d0caaeSpatrick 
5476d0caaeSpatrick #endif // _LIBCPP___UTILITY_SWAP_H
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