xref: /freebsd-src/contrib/llvm-project/libcxx/include/__algorithm/ranges_rotate_copy.h (revision cb14a3fe5122c879eae1fb480ed7ce82a699ddb6)
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_ROTATE_COPY_H
10 #define _LIBCPP___ALGORITHM_RANGES_ROTATE_COPY_H
11 
12 #include <__algorithm/in_out_result.h>
13 #include <__algorithm/ranges_copy.h>
14 #include <__config>
15 #include <__iterator/concepts.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 #endif
24 
25 #if _LIBCPP_STD_VER >= 20
26 
27 _LIBCPP_BEGIN_NAMESPACE_STD
28 
29 namespace ranges {
30 
31 template <class _InIter, class _OutIter>
32 using rotate_copy_result = in_out_result<_InIter, _OutIter>;
33 
34 namespace __rotate_copy {
35 struct __fn {
36   template <forward_iterator _InIter, sentinel_for<_InIter> _Sent, weakly_incrementable _OutIter>
37     requires indirectly_copyable<_InIter, _OutIter>
38   _LIBCPP_HIDE_FROM_ABI constexpr rotate_copy_result<_InIter, _OutIter>
39   operator()(_InIter __first, _InIter __middle, _Sent __last, _OutIter __result) const {
40     auto __res1 = ranges::copy(__middle, __last, std::move(__result));
41     auto __res2 = ranges::copy(__first, __middle, std::move(__res1.out));
42     return {std::move(__res1.in), std::move(__res2.out)};
43   }
44 
45   template <forward_range _Range, weakly_incrementable _OutIter>
46     requires indirectly_copyable<iterator_t<_Range>, _OutIter>
47   _LIBCPP_HIDE_FROM_ABI constexpr rotate_copy_result<borrowed_iterator_t<_Range>, _OutIter>
48   operator()(_Range&& __range, iterator_t<_Range> __middle, _OutIter __result) const {
49     return (*this)(ranges::begin(__range), std::move(__middle), ranges::end(__range), std::move(__result));
50   }
51 };
52 } // namespace __rotate_copy
53 
54 inline namespace __cpo {
55 inline constexpr auto rotate_copy = __rotate_copy::__fn{};
56 } // namespace __cpo
57 } // namespace ranges
58 
59 _LIBCPP_END_NAMESPACE_STD
60 
61 #endif // _LIBCPP_STD_VER >= 20
62 
63 #endif // _LIBCPP___ALGORITHM_RANGES_ROTATE_COPY_H
64