xref: /freebsd-src/contrib/llvm-project/libcxx/include/__utility/swap.h (revision fe6060f10f634930ff71b7c50291ddc610da2475)
1*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
2*fe6060f1SDimitry Andric //
3*fe6060f1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*fe6060f1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
5*fe6060f1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*fe6060f1SDimitry Andric //
7*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
8*fe6060f1SDimitry Andric 
9*fe6060f1SDimitry Andric #ifndef _LIBCPP___UTILITY_SWAP_H
10*fe6060f1SDimitry Andric #define _LIBCPP___UTILITY_SWAP_H
11*fe6060f1SDimitry Andric 
12*fe6060f1SDimitry Andric #include <__config>
13*fe6060f1SDimitry Andric #include <__utility/declval.h>
14*fe6060f1SDimitry Andric #include <__utility/move.h>
15*fe6060f1SDimitry Andric #include <type_traits>
16*fe6060f1SDimitry Andric #include <cstddef>
17*fe6060f1SDimitry Andric 
18*fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19*fe6060f1SDimitry Andric #pragma GCC system_header
20*fe6060f1SDimitry Andric #endif
21*fe6060f1SDimitry Andric 
22*fe6060f1SDimitry Andric _LIBCPP_PUSH_MACROS
23*fe6060f1SDimitry Andric #include <__undef_macros>
24*fe6060f1SDimitry Andric 
25*fe6060f1SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
26*fe6060f1SDimitry Andric 
27*fe6060f1SDimitry Andric #ifndef _LIBCPP_CXX03_LANG
28*fe6060f1SDimitry Andric template <class _Tp>
29*fe6060f1SDimitry Andric using __swap_result_t = typename enable_if<is_move_constructible<_Tp>::value && is_move_assignable<_Tp>::value>::type;
30*fe6060f1SDimitry Andric #else
31*fe6060f1SDimitry Andric template <class>
32*fe6060f1SDimitry Andric using __swap_result_t = void;
33*fe6060f1SDimitry Andric #endif
34*fe6060f1SDimitry Andric 
35*fe6060f1SDimitry Andric template <class _Tp>
36*fe6060f1SDimitry Andric inline _LIBCPP_INLINE_VISIBILITY __swap_result_t<_Tp> _LIBCPP_CONSTEXPR_AFTER_CXX17 swap(_Tp& __x, _Tp& __y)
37*fe6060f1SDimitry Andric     _NOEXCEPT_(is_nothrow_move_constructible<_Tp>::value&& is_nothrow_move_assignable<_Tp>::value) {
38*fe6060f1SDimitry Andric   _Tp __t(_VSTD::move(__x));
39*fe6060f1SDimitry Andric   __x = _VSTD::move(__y);
40*fe6060f1SDimitry Andric   __y = _VSTD::move(__t);
41*fe6060f1SDimitry Andric }
42*fe6060f1SDimitry Andric 
43*fe6060f1SDimitry Andric template <class _Tp, size_t _Np>
44*fe6060f1SDimitry Andric inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 typename enable_if<__is_swappable<_Tp>::value>::type
45*fe6060f1SDimitry Andric swap(_Tp (&__a)[_Np], _Tp (&__b)[_Np]) _NOEXCEPT_(__is_nothrow_swappable<_Tp>::value) {
46*fe6060f1SDimitry Andric   for (size_t __i = 0; __i != _Np; ++__i) {
47*fe6060f1SDimitry Andric     swap(__a[__i], __b[__i]);
48*fe6060f1SDimitry Andric   }
49*fe6060f1SDimitry Andric }
50*fe6060f1SDimitry Andric 
51*fe6060f1SDimitry Andric _LIBCPP_END_NAMESPACE_STD
52*fe6060f1SDimitry Andric 
53*fe6060f1SDimitry Andric _LIBCPP_POP_MACROS
54*fe6060f1SDimitry Andric 
55*fe6060f1SDimitry Andric #endif // _LIBCPP___UTILITY_SWAP_H
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