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_EQUAL_H 10 #define _LIBCPP___ALGORITHM_RANGES_EQUAL_H 11 12 #include <__config> 13 #include <__functional/identity.h> 14 #include <__functional/invoke.h> 15 #include <__functional/ranges_operations.h> 16 #include <__iterator/concepts.h> 17 #include <__iterator/distance.h> 18 #include <__iterator/indirectly_comparable.h> 19 #include <__ranges/access.h> 20 #include <__ranges/concepts.h> 21 #include <__utility/move.h> 22 23 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 24 # pragma GCC system_header 25 #endif 26 27 #if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES) 28 29 _LIBCPP_BEGIN_NAMESPACE_STD 30 31 namespace ranges { 32 namespace __equal { 33 struct __fn { 34 private: 35 template <class _Iter1, class _Sent1, 36 class _Iter2, class _Sent2, 37 class _Pred, 38 class _Proj1, 39 class _Proj2> 40 _LIBCPP_HIDE_FROM_ABI constexpr static 41 bool __equal_impl(_Iter1 __first1, _Sent1 __last1, 42 _Iter2 __first2, _Sent2 __last2, 43 _Pred& __pred, 44 _Proj1& __proj1, 45 _Proj2& __proj2) { 46 while (__first1 != __last1 && __first2 != __last2) { 47 if (!std::invoke(__pred, std::invoke(__proj1, *__first1), std::invoke(__proj2, *__first2))) 48 return false; 49 ++__first1; 50 ++__first2; 51 } 52 return __first1 == __last1 && __first2 == __last2; 53 } 54 55 public: 56 57 template <input_iterator _Iter1, sentinel_for<_Iter1> _Sent1, 58 input_iterator _Iter2, sentinel_for<_Iter2> _Sent2, 59 class _Pred = ranges::equal_to, 60 class _Proj1 = identity, 61 class _Proj2 = identity> 62 requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2> 63 _LIBCPP_HIDE_FROM_ABI constexpr 64 bool operator()(_Iter1 __first1, _Sent1 __last1, 65 _Iter2 __first2, _Sent2 __last2, 66 _Pred __pred = {}, 67 _Proj1 __proj1 = {}, 68 _Proj2 __proj2 = {}) const { 69 if constexpr (sized_sentinel_for<_Sent1, _Iter1> && sized_sentinel_for<_Sent2, _Iter2>) { 70 if (__last1 - __first1 != __last2 - __first2) 71 return false; 72 } 73 return __equal_impl(std::move(__first1), std::move(__last1), 74 std::move(__first2), std::move(__last2), 75 __pred, 76 __proj1, 77 __proj2); 78 } 79 80 template <input_range _Range1, 81 input_range _Range2, 82 class _Pred = ranges::equal_to, 83 class _Proj1 = identity, 84 class _Proj2 = identity> 85 requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2> 86 _LIBCPP_HIDE_FROM_ABI constexpr 87 bool operator()(_Range1&& __range1, 88 _Range2&& __range2, 89 _Pred __pred = {}, 90 _Proj1 __proj1 = {}, 91 _Proj2 __proj2 = {}) const { 92 if constexpr (sized_range<_Range1> && sized_range<_Range2>) { 93 if (ranges::distance(__range1) != ranges::distance(__range2)) 94 return false; 95 } 96 return __equal_impl(ranges::begin(__range1), ranges::end(__range1), 97 ranges::begin(__range2), ranges::end(__range2), 98 __pred, 99 __proj1, 100 __proj2); 101 return false; 102 } 103 }; 104 } // namespace __equal 105 106 inline namespace __cpo { 107 inline constexpr auto equal = __equal::__fn{}; 108 } // namespace __cpo 109 } // namespace ranges 110 111 _LIBCPP_END_NAMESPACE_STD 112 113 #endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES) 114 115 #endif // _LIBCPP___ALGORITHM_RANGES_EQUAL_H 116