libcxx/include/__cxx03/__algorithm/ranges_next_permutation.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_NEXT_PERMUTATION_H
  10 #define _LIBCPP___ALGORITHM_RANGES_NEXT_PERMUTATION_H
  11
  12 #include <__cxx03/__algorithm/in_found_result.h>
  13 #include <__cxx03/__algorithm/iterator_operations.h>
  14 #include <__cxx03/__algorithm/make_projected.h>
  15 #include <__cxx03/__algorithm/next_permutation.h>
  16 #include <__cxx03/__config>
  17 #include <__cxx03/__functional/identity.h>
  18 #include <__cxx03/__functional/ranges_operations.h>
  19 #include <__cxx03/__iterator/concepts.h>
  20 #include <__cxx03/__iterator/sortable.h>
  21 #include <__cxx03/__ranges/access.h>
  22 #include <__cxx03/__ranges/concepts.h>
  23 #include <__cxx03/__ranges/dangling.h>
  24 #include <__cxx03/__utility/move.h>
  25 #include <__cxx03/__utility/pair.h>
  26
  27 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  28 #  pragma GCC system_header
  29 #endif
  30
  31 _LIBCPP_PUSH_MACROS
  32 #include <__cxx03/__undef_macros>
  33
  34 #if _LIBCPP_STD_VER >= 20
  35
  36 _LIBCPP_BEGIN_NAMESPACE_STD
  37
  38 namespace ranges {
  39
  40 template <class _InIter>
  41 using next_permutation_result = in_found_result<_InIter>;
  42
  43 namespace __next_permutation {
  44
  45 struct __fn {
  46   template <bidirectional_iterator _Iter, sentinel_for<_Iter> _Sent, class _Comp = ranges::less, class _Proj = identity>
  47     requires sortable<_Iter, _Comp, _Proj>
  48   _LIBCPP_HIDE_FROM_ABI constexpr next_permutation_result<_Iter>
  49   operator()(_Iter __first, _Sent __last, _Comp __comp = {}, _Proj __proj = {}) const {
  50     auto __result = std::__next_permutation<_RangeAlgPolicy>(
  51         std::move(__first), std::move(__last), std::__make_projected(__comp, __proj));
  52     return {std::move(__result.first), std::move(__result.second)};
  53   }
  54
  55   template <bidirectional_range _Range, class _Comp = ranges::less, class _Proj = identity>
  56     requires sortable<iterator_t<_Range>, _Comp, _Proj>
  57   _LIBCPP_HIDE_FROM_ABI constexpr next_permutation_result<borrowed_iterator_t<_Range>>
  58   operator()(_Range&& __range, _Comp __comp = {}, _Proj __proj = {}) const {
  59     auto __result = std::__next_permutation<_RangeAlgPolicy>(
  60         ranges::begin(__range), ranges::end(__range), std::__make_projected(__comp, __proj));
  61     return {std::move(__result.first), std::move(__result.second)};
  62   }
  63 };
  64
  65 } // namespace __next_permutation
  66
  67 inline namespace __cpo {
  68 constexpr inline auto next_permutation = __next_permutation::__fn{};
  69 } // namespace __cpo
  70 } // namespace ranges
  71
  72 _LIBCPP_END_NAMESPACE_STD
  73
  74 #endif // _LIBCPP_STD_VER >= 20
  75
  76 _LIBCPP_POP_MACROS
  77
  78 #endif // _LIBCPP___ALGORITHM_RANGES_NEXT_PERMUTATION_H