__cxx03/__algorithm/ranges_ends_with.h

0001 //===----------------------------------------------------------------------===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008
0009 #ifndef _LIBCPP___CXX03___ALGORITHM_RANGES_ENDS_WITH_H
0010 #define _LIBCPP___CXX03___ALGORITHM_RANGES_ENDS_WITH_H
0011
0012 #include <__cxx03/__algorithm/ranges_equal.h>
0013 #include <__cxx03/__algorithm/ranges_starts_with.h>
0014 #include <__cxx03/__config>
0015 #include <__cxx03/__functional/identity.h>
0016 #include <__cxx03/__functional/ranges_operations.h>
0017 #include <__cxx03/__functional/reference_wrapper.h>
0018 #include <__cxx03/__iterator/advance.h>
0019 #include <__cxx03/__iterator/concepts.h>
0020 #include <__cxx03/__iterator/distance.h>
0021 #include <__cxx03/__iterator/indirectly_comparable.h>
0022 #include <__cxx03/__iterator/reverse_iterator.h>
0023 #include <__cxx03/__ranges/access.h>
0024 #include <__cxx03/__ranges/concepts.h>
0025 #include <__cxx03/__utility/move.h>
0026
0027 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0028 #  pragma GCC system_header
0029 #endif
0030
0031 _LIBCPP_PUSH_MACROS
0032 #include <__cxx03/__undef_macros>
0033
0034 #if _LIBCPP_STD_VER >= 23
0035
0036 _LIBCPP_BEGIN_NAMESPACE_STD
0037
0038 namespace ranges {
0039 namespace __ends_with {
0040 struct __fn {
0041   template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
0042   _LIBCPP_HIDE_FROM_ABI static constexpr bool __ends_with_fn_impl_bidirectional(
0043       _Iter1 __first1,
0044       _Sent1 __last1,
0045       _Iter2 __first2,
0046       _Sent2 __last2,
0047       _Pred& __pred,
0048       _Proj1& __proj1,
0049       _Proj2& __proj2) {
0050     auto __rbegin1 = std::make_reverse_iterator(__last1);
0051     auto __rend1   = std::make_reverse_iterator(__first1);
0052     auto __rbegin2 = std::make_reverse_iterator(__last2);
0053     auto __rend2   = std::make_reverse_iterator(__first2);
0054     return ranges::starts_with(
0055         __rbegin1, __rend1, __rbegin2, __rend2, std::ref(__pred), std::ref(__proj1), std::ref(__proj2));
0056   }
0057
0058   template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
0059   _LIBCPP_HIDE_FROM_ABI static constexpr bool __ends_with_fn_impl(
0060       _Iter1 __first1,
0061       _Sent1 __last1,
0062       _Iter2 __first2,
0063       _Sent2 __last2,
0064       _Pred& __pred,
0065       _Proj1& __proj1,
0066       _Proj2& __proj2) {
0067     if constexpr (std::bidirectional_iterator<_Sent1> && std::bidirectional_iterator<_Sent2> &&
0068                   (!std::random_access_iterator<_Sent1>) && (!std::random_access_iterator<_Sent2>)) {
0069       return __ends_with_fn_impl_bidirectional(__first1, __last1, __first2, __last2, __pred, __proj1, __proj2);
0070
0071     } else {
0072       auto __n1 = ranges::distance(__first1, __last1);
0073       auto __n2 = ranges::distance(__first2, __last2);
0074       if (__n2 == 0)
0075         return true;
0076       if (__n2 > __n1)
0077         return false;
0078
0079       return __ends_with_fn_impl_with_offset(
0080           std::move(__first1),
0081           std::move(__last1),
0082           std::move(__first2),
0083           std::move(__last2),
0084           __pred,
0085           __proj1,
0086           __proj2,
0087           __n1 - __n2);
0088     }
0089   }
0090
0091   template <class _Iter1,
0092             class _Sent1,
0093             class _Iter2,
0094             class _Sent2,
0095             class _Pred,
0096             class _Proj1,
0097             class _Proj2,
0098             class _Offset>
0099   static _LIBCPP_HIDE_FROM_ABI constexpr bool __ends_with_fn_impl_with_offset(
0100       _Iter1 __first1,
0101       _Sent1 __last1,
0102       _Iter2 __first2,
0103       _Sent2 __last2,
0104       _Pred& __pred,
0105       _Proj1& __proj1,
0106       _Proj2& __proj2,
0107       _Offset __offset) {
0108     if constexpr (std::bidirectional_iterator<_Sent1> && std::bidirectional_iterator<_Sent2> &&
0109                   !std::random_access_iterator<_Sent1> && !std::random_access_iterator<_Sent2>) {
0110       return __ends_with_fn_impl_bidirectional(
0111           std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
0112
0113     } else {
0114       ranges::advance(__first1, __offset);
0115       return ranges::equal(
0116           std::move(__first1),
0117           std::move(__last1),
0118           std::move(__first2),
0119           std::move(__last2),
0120           std::ref(__pred),
0121           std::ref(__proj1),
0122           std::ref(__proj2));
0123     }
0124   }
0125
0126   template <input_iterator _Iter1,
0127             sentinel_for<_Iter1> _Sent1,
0128             input_iterator _Iter2,
0129             sentinel_for<_Iter2> _Sent2,
0130             class _Pred  = ranges::equal_to,
0131             class _Proj1 = identity,
0132             class _Proj2 = identity>
0133     requires(forward_iterator<_Iter1> || sized_sentinel_for<_Sent1, _Iter1>) &&
0134             (forward_iterator<_Iter2> || sized_sentinel_for<_Sent2, _Iter2>) &&
0135             indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
0136   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
0137       _Iter1 __first1,
0138       _Sent1 __last1,
0139       _Iter2 __first2,
0140       _Sent2 __last2,
0141       _Pred __pred   = {},
0142       _Proj1 __proj1 = {},
0143       _Proj2 __proj2 = {}) const {
0144     return __ends_with_fn_impl(
0145         std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
0146   }
0147
0148   template <input_range _Range1,
0149             input_range _Range2,
0150             class _Pred  = ranges::equal_to,
0151             class _Proj1 = identity,
0152             class _Proj2 = identity>
0153     requires(forward_range<_Range1> || sized_range<_Range1>) && (forward_range<_Range2> || sized_range<_Range2>) &&
0154             indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
0155   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
0156       _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
0157     if constexpr (sized_range<_Range1> && sized_range<_Range2>) {
0158       auto __n1 = ranges::size(__range1);
0159       auto __n2 = ranges::size(__range2);
0160       if (__n2 == 0)
0161         return true;
0162       if (__n2 > __n1)
0163         return false;
0164       auto __offset = __n1 - __n2;
0165
0166       return __ends_with_fn_impl_with_offset(
0167           ranges::begin(__range1),
0168           ranges::end(__range1),
0169           ranges::begin(__range2),
0170           ranges::end(__range2),
0171           __pred,
0172           __proj1,
0173           __proj2,
0174           __offset);
0175
0176     } else {
0177       return __ends_with_fn_impl(
0178           ranges::begin(__range1),
0179           ranges::end(__range1),
0180           ranges::begin(__range2),
0181           ranges::end(__range2),
0182           __pred,
0183           __proj1,
0184           __proj2);
0185     }
0186   }
0187 };
0188 } // namespace __ends_with
0189
0190 inline namespace __cpo {
0191 inline constexpr auto ends_with = __ends_with::__fn{};
0192 } // namespace __cpo
0193 } // namespace ranges
0194
0195 _LIBCPP_END_NAMESPACE_STD
0196
0197 #endif // _LIBCPP_STD_VER >= 23
0198
0199 _LIBCPP_POP_MACROS
0200
0201 #endif // _LIBCPP___CXX03___ALGORITHM_RANGES_ENDS_WITH_H