v1/__algorithm/swap_ranges.h

0001 //===----------------------------------------------------------------------===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008
0009 #ifndef _LIBCPP___ALGORITHM_SWAP_RANGES_H
0010 #define _LIBCPP___ALGORITHM_SWAP_RANGES_H
0011
0012 #include <__algorithm/iterator_operations.h>
0013 #include <__config>
0014 #include <__utility/move.h>
0015 #include <__utility/pair.h>
0016
0017 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0018 #  pragma GCC system_header
0019 #endif
0020
0021 _LIBCPP_PUSH_MACROS
0022 #include <__undef_macros>
0023
0024 _LIBCPP_BEGIN_NAMESPACE_STD
0025
0026 // 2+2 iterators: the shorter size will be used.
0027 template <class _AlgPolicy, class _ForwardIterator1, class _Sentinel1, class _ForwardIterator2, class _Sentinel2>
0028 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator1, _ForwardIterator2>
0029 __swap_ranges(_ForwardIterator1 __first1, _Sentinel1 __last1, _ForwardIterator2 __first2, _Sentinel2 __last2) {
0030   while (__first1 != __last1 && __first2 != __last2) {
0031     _IterOps<_AlgPolicy>::iter_swap(__first1, __first2);
0032     ++__first1;
0033     ++__first2;
0034   }
0035
0036   return pair<_ForwardIterator1, _ForwardIterator2>(std::move(__first1), std::move(__first2));
0037 }
0038
0039 // 2+1 iterators: size2 >= size1.
0040 template <class _AlgPolicy, class _ForwardIterator1, class _Sentinel1, class _ForwardIterator2>
0041 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator1, _ForwardIterator2>
0042 __swap_ranges(_ForwardIterator1 __first1, _Sentinel1 __last1, _ForwardIterator2 __first2) {
0043   while (__first1 != __last1) {
0044     _IterOps<_AlgPolicy>::iter_swap(__first1, __first2);
0045     ++__first1;
0046     ++__first2;
0047   }
0048
0049   return pair<_ForwardIterator1, _ForwardIterator2>(std::move(__first1), std::move(__first2));
0050 }
0051
0052 template <class _ForwardIterator1, class _ForwardIterator2>
0053 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator2
0054 swap_ranges(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2) {
0055   return std::__swap_ranges<_ClassicAlgPolicy>(std::move(__first1), std::move(__last1), std::move(__first2)).second;
0056 }
0057
0058 _LIBCPP_END_NAMESPACE_STD
0059
0060 _LIBCPP_POP_MACROS
0061
0062 #endif // _LIBCPP___ALGORITHM_SWAP_RANGES_H