xref: /llvm-project/libcxx/include/__algorithm/ranges_rotate_copy.h (revision d10dc5a06fac4dcabf2264c64c8672c6f6ae36fb)
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 _LIBCPP_PUSH_MACROS
26 #include <__undef_macros>
27 
28 #if _LIBCPP_STD_VER >= 20
29 
30 _LIBCPP_BEGIN_NAMESPACE_STD
31 
32 namespace ranges {
33 
34 template <class _InIter, class _OutIter>
35 using rotate_copy_result = in_out_result<_InIter, _OutIter>;
36 
37 struct __rotate_copy {
38   template <forward_iterator _InIter, sentinel_for<_InIter> _Sent, weakly_incrementable _OutIter>
39     requires indirectly_copyable<_InIter, _OutIter>
40   _LIBCPP_HIDE_FROM_ABI constexpr rotate_copy_result<_InIter, _OutIter>
41   operator()(_InIter __first, _InIter __middle, _Sent __last, _OutIter __result) const {
42     auto __res1 = ranges::copy(__middle, __last, std::move(__result));
43     auto __res2 = ranges::copy(__first, __middle, std::move(__res1.out));
44     return {std::move(__res1.in), std::move(__res2.out)};
45   }
46 
47   template <forward_range _Range, weakly_incrementable _OutIter>
48     requires indirectly_copyable<iterator_t<_Range>, _OutIter>
49   _LIBCPP_HIDE_FROM_ABI constexpr rotate_copy_result<borrowed_iterator_t<_Range>, _OutIter>
50   operator()(_Range&& __range, iterator_t<_Range> __middle, _OutIter __result) const {
51     return (*this)(ranges::begin(__range), std::move(__middle), ranges::end(__range), std::move(__result));
52   }
53 };
54 
55 inline namespace __cpo {
56 inline constexpr auto rotate_copy = __rotate_copy{};
57 } // namespace __cpo
58 } // namespace ranges
59 
60 _LIBCPP_END_NAMESPACE_STD
61 
62 #endif // _LIBCPP_STD_VER >= 20
63 
64 _LIBCPP_POP_MACROS
65 
66 #endif // _LIBCPP___ALGORITHM_RANGES_ROTATE_COPY_H
67