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_H
10 #define _LIBCPP___ALGORITHM_RANGES_ROTATE_H
11 
12 #include <__algorithm/iterator_operations.h>
13 #include <__algorithm/ranges_iterator_concept.h>
14 #include <__algorithm/rotate.h>
15 #include <__config>
16 #include <__iterator/concepts.h>
17 #include <__iterator/iterator_traits.h>
18 #include <__iterator/permutable.h>
19 #include <__ranges/access.h>
20 #include <__ranges/concepts.h>
21 #include <__ranges/subrange.h>
22 #include <__utility/move.h>
23 
24 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
25 #  pragma GCC system_header
26 #endif
27 
28 #if _LIBCPP_STD_VER >= 20
29 
30 _LIBCPP_BEGIN_NAMESPACE_STD
31 
32 namespace ranges {
33 namespace __rotate {
34 
35 struct __fn {
36   template <class _Iter, class _Sent>
37   _LIBCPP_HIDE_FROM_ABI constexpr static subrange<_Iter> __rotate_fn_impl(_Iter __first, _Iter __middle, _Sent __last) {
38     auto __ret = std::__rotate<_RangeAlgPolicy>(std::move(__first), std::move(__middle), std::move(__last));
39     return {std::move(__ret.first), std::move(__ret.second)};
40   }
41 
42   template <permutable _Iter, sentinel_for<_Iter> _Sent>
43   _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter> operator()(_Iter __first, _Iter __middle, _Sent __last) const {
44     return __rotate_fn_impl(std::move(__first), std::move(__middle), std::move(__last));
45   }
46 
47   template <forward_range _Range>
48     requires permutable<iterator_t<_Range>>
49   _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range>
50   operator()(_Range&& __range, iterator_t<_Range> __middle) const {
51     return __rotate_fn_impl(ranges::begin(__range), std::move(__middle), ranges::end(__range));
52   }
53 };
54 
55 } // namespace __rotate
56 
57 inline namespace __cpo {
58 inline constexpr auto rotate = __rotate::__fn{};
59 } // namespace __cpo
60 } // namespace ranges
61 
62 _LIBCPP_END_NAMESPACE_STD
63 
64 #endif // _LIBCPP_STD_VER >= 20
65 
66 #endif // _LIBCPP___ALGORITHM_RANGES_ROTATE_H
67