xref: /llvm-project/libcxx/include/__algorithm/ranges_is_permutation.h (revision d10dc5a06fac4dcabf2264c64c8672c6f6ae36fb)

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP___ALGORITHM_RANGES_IS_PERMUTATION_H
#define _LIBCPP___ALGORITHM_RANGES_IS_PERMUTATION_H

#include <__algorithm/is_permutation.h>
#include <__algorithm/iterator_operations.h>
#include <__config>
#include <__functional/identity.h>
#include <__functional/ranges_operations.h>
#include <__iterator/concepts.h>
#include <__iterator/distance.h>
#include <__iterator/projected.h>
#include <__ranges/access.h>
#include <__ranges/concepts.h>
#include <__utility/move.h>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#  pragma GCC system_header
#endif

_LIBCPP_PUSH_MACROS
#include <__undef_macros>

#if _LIBCPP_STD_VER >= 20

_LIBCPP_BEGIN_NAMESPACE_STD

namespace ranges {
struct __is_permutation {
  template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Proj1, class _Proj2, class _Pred>
  _LIBCPP_HIDE_FROM_ABI constexpr static bool __is_permutation_func_impl(
      _Iter1 __first1,
      _Sent1 __last1,
      _Iter2 __first2,
      _Sent2 __last2,
      _Pred& __pred,
      _Proj1& __proj1,
      _Proj2& __proj2) {
    return std::__is_permutation<_RangeAlgPolicy>(
        std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
  }

  template <
      forward_iterator _Iter1,
      sentinel_for<_Iter1> _Sent1,
      forward_iterator _Iter2,
      sentinel_for<_Iter2> _Sent2,
      class _Proj1                                                                              = identity,
      class _Proj2                                                                              = identity,
      indirect_equivalence_relation<projected<_Iter1, _Proj1>, projected<_Iter2, _Proj2>> _Pred = ranges::equal_to>
  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
      _Iter1 __first1,
      _Sent1 __last1,
      _Iter2 __first2,
      _Sent2 __last2,
      _Pred __pred   = {},
      _Proj1 __proj1 = {},
      _Proj2 __proj2 = {}) const {
    return __is_permutation_func_impl(
        std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
  }

  template <forward_range _Range1,
            forward_range _Range2,
            class _Proj1                                                                = identity,
            class _Proj2                                                                = identity,
            indirect_equivalence_relation<projected<iterator_t<_Range1>, _Proj1>,
                                          projected<iterator_t<_Range2>, _Proj2>> _Pred = ranges::equal_to>
  [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
      _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
    if constexpr (sized_range<_Range1> && sized_range<_Range2>) {
      if (ranges::distance(__range1) != ranges::distance(__range2))
        return false;
    }

    return __is_permutation_func_impl(
        ranges::begin(__range1),
        ranges::end(__range1),
        ranges::begin(__range2),
        ranges::end(__range2),
        __pred,
        __proj1,
        __proj2);
  }
};

inline namespace __cpo {
inline constexpr auto is_permutation = __is_permutation{};
} // namespace __cpo
} // namespace ranges

_LIBCPP_END_NAMESPACE_STD

#endif // _LIBCPP_STD_VER >= 20

_LIBCPP_POP_MACROS

#endif // _LIBCPP___ALGORITHM_RANGES_IS_PERMUTATION_H