libcxx/include/__algorithm/ranges_rotate_copy.h

   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 <__iterator/reverse_iterator.h>
  17 #include <__ranges/access.h>
  18 #include <__ranges/concepts.h>
  19 #include <__ranges/dangling.h>
  20 #include <__utility/move.h>
  21
  22 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  23 #  pragma GCC system_header
  24 #endif
  25
  26 #if _LIBCPP_STD_VER >= 20
  27
  28 _LIBCPP_BEGIN_NAMESPACE_STD
  29
  30 namespace ranges {
  31
  32 template <class _InIter, class _OutIter>
  33 using rotate_copy_result = in_out_result<_InIter, _OutIter>;
  34
  35 namespace __rotate_copy {
  36 struct __fn {
  37   template <bidirectional_iterator _InIter, sentinel_for<_InIter> _Sent, weakly_incrementable _OutIter>
  38     requires indirectly_copyable<_InIter, _OutIter>
  39   _LIBCPP_HIDE_FROM_ABI constexpr rotate_copy_result<_InIter, _OutIter>
  40   operator()(_InIter __first, _InIter __middle, _Sent __last, _OutIter __result) const {
  41     auto __res1 = ranges::copy(__middle, __last, std::move(__result));
  42     auto __res2 = ranges::copy(__first, __middle, std::move(__res1.out));
  43     return {std::move(__res1.in), std::move(__res2.out)};
  44   }
  45
  46   template <bidirectional_range _Range, weakly_incrementable _OutIter>
  47     requires indirectly_copyable<iterator_t<_Range>, _OutIter>
  48   _LIBCPP_HIDE_FROM_ABI constexpr rotate_copy_result<borrowed_iterator_t<_Range>, _OutIter>
  49   operator()(_Range&& __range, iterator_t<_Range> __middle, _OutIter __result) const {
  50     return (*this)(ranges::begin(__range), std::move(__middle), ranges::end(__range), std::move(__result));
  51   }
  52 };
  53 } // namespace __rotate_copy
  54
  55 inline namespace __cpo {
  56 inline constexpr auto rotate_copy = __rotate_copy::__fn{};
  57 } // namespace __cpo
  58 } // namespace ranges
  59
  60 _LIBCPP_END_NAMESPACE_STD
  61
  62 #endif // _LIBCPP_STD_VER >= 20
  63
  64 #endif // _LIBCPP___ALGORITHM_RANGES_ROTATE_COPY_H