xref: /llvm-project/libcxx/include/__algorithm/ranges_swap_ranges.h (revision 5aaefa510ef055e8f044ca89e352d4313f3aba49)
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___ALGORITHM_RANGES_SWAP_RANGES_H
10 #define _LIBCPP___ALGORITHM_RANGES_SWAP_RANGES_H
11 
12 #include <__algorithm/in_in_result.h>
13 #include <__config>
14 #include <__iterator/concepts.h>
15 #include <__iterator/iter_swap.h>
16 #include <__ranges/access.h>
17 #include <__ranges/concepts.h>
18 #include <__ranges/dangling.h>
19 #include <__utility/move.h>
20 
21 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
22 #  pragma GCC system_header
23 #  pragma clang include_instead(<algorithm>)
24 #endif
25 
26 #ifndef _LIBCPP_HAS_NO_CONCEPTS
27 
28 _LIBCPP_BEGIN_NAMESPACE_STD
29 
30 namespace ranges {
31 
32 template <class _I1, class _I2>
33 using swap_ranges_result = in_in_result<_I1, _I2>;
34 
35 namespace __swap_ranges {
36 struct __fn {
37   template <input_iterator _I1, sentinel_for<_I1> _S1,
38             input_iterator _I2, sentinel_for<_I2> _S2>
39     requires indirectly_swappable<_I1, _I2>
40   _LIBCPP_HIDE_FROM_ABI constexpr swap_ranges_result<_I1, _I2>
41   operator()(_I1 __first1, _S1 __last1, _I2 __first2, _S2 __last2) const {
42     while (__first1 != __last1 && __first2 != __last2) {
43       ranges::iter_swap(__first1, __first2);
44       ++__first1;
45       ++__first2;
46     }
47     return {_VSTD::move(__first1), _VSTD::move(__first2)};
48   }
49 
50   template <input_range _R1, input_range _R2>
51     requires indirectly_swappable<iterator_t<_R1>, iterator_t<_R2>>
52   _LIBCPP_HIDE_FROM_ABI constexpr
53   swap_ranges_result<borrowed_iterator_t<_R1>, borrowed_iterator_t<_R2>>
54   operator()(_R1&& __r1, _R2&& __r2) const {
55     return operator()(ranges::begin(__r1), ranges::end(__r1),
56                       ranges::begin(__r2), ranges::end(__r2));
57   }
58 };
59 } // namespace __swap_ranges
60 
61 inline namespace __cpo {
62   inline constexpr auto swap_ranges = __swap_ranges::__fn{};
63 } // namespace __cpo
64 } // namespace ranges
65 
66 _LIBCPP_END_NAMESPACE_STD
67 
68 #endif // _LIBCPP_HAS_NO_RANGES
69 
70 #endif // _LIBCPP___ALGORITHM_RANGES_SWAP_RANGES_H
71