xref: /freebsd-src/contrib/llvm-project/libcxx/include/__algorithm/ranges_ends_with.h (revision 1db9f3b21e39176dd5b67cf8ac378633b172463e)
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_ENDS_WITH_H
10 #define _LIBCPP___ALGORITHM_RANGES_ENDS_WITH_H
11 
12 #include <__algorithm/ranges_equal.h>
13 #include <__algorithm/ranges_starts_with.h>
14 #include <__config>
15 #include <__functional/identity.h>
16 #include <__functional/ranges_operations.h>
17 #include <__functional/reference_wrapper.h>
18 #include <__iterator/advance.h>
19 #include <__iterator/concepts.h>
20 #include <__iterator/distance.h>
21 #include <__iterator/indirectly_comparable.h>
22 #include <__iterator/reverse_iterator.h>
23 #include <__ranges/access.h>
24 #include <__ranges/concepts.h>
25 #include <__utility/move.h>
26 
27 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
28 #  pragma GCC system_header
29 #endif
30 
31 #if _LIBCPP_STD_VER >= 23
32 
33 _LIBCPP_BEGIN_NAMESPACE_STD
34 
35 namespace ranges {
36 namespace __ends_with {
37 struct __fn {
38   template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
39   static _LIBCPP_HIDE_FROM_ABI constexpr bool __ends_with_fn_impl_bidirectional(
40       _Iter1 __first1,
41       _Sent1 __last1,
42       _Iter2 __first2,
43       _Sent2 __last2,
44       _Pred& __pred,
45       _Proj1& __proj1,
46       _Proj2& __proj2) {
47     auto __rbegin1 = std::make_reverse_iterator(__last1);
48     auto __rend1   = std::make_reverse_iterator(__first1);
49     auto __rbegin2 = std::make_reverse_iterator(__last2);
50     auto __rend2   = std::make_reverse_iterator(__first2);
51     return ranges::starts_with(
52         __rbegin1, __rend1, __rbegin2, __rend2, std::ref(__pred), std::ref(__proj1), std::ref(__proj2));
53   }
54 
55   template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
56   static _LIBCPP_HIDE_FROM_ABI constexpr bool __ends_with_fn_impl(
57       _Iter1 __first1,
58       _Sent1 __last1,
59       _Iter2 __first2,
60       _Sent2 __last2,
61       _Pred& __pred,
62       _Proj1& __proj1,
63       _Proj2& __proj2) {
64     if constexpr (std::bidirectional_iterator<_Sent1> && std::bidirectional_iterator<_Sent2> &&
65                   (!std::random_access_iterator<_Sent1>)&&(!std::random_access_iterator<_Sent2>)) {
66       return __ends_with_fn_impl_bidirectional(__first1, __last1, __first2, __last2, __pred, __proj1, __proj2);
67 
68     } else {
69       auto __n1 = ranges::distance(__first1, __last1);
70       auto __n2 = ranges::distance(__first2, __last2);
71       if (__n2 == 0)
72         return true;
73       if (__n2 > __n1)
74         return false;
75 
76       return __ends_with_fn_impl_with_offset(
77           std::move(__first1),
78           std::move(__last1),
79           std::move(__first2),
80           std::move(__last2),
81           __pred,
82           __proj1,
83           __proj2,
84           __n1 - __n2);
85     }
86   }
87 
88   template <class _Iter1,
89             class _Sent1,
90             class _Iter2,
91             class _Sent2,
92             class _Pred,
93             class _Proj1,
94             class _Proj2,
95             class _Offset>
96   static _LIBCPP_HIDE_FROM_ABI constexpr bool __ends_with_fn_impl_with_offset(
97       _Iter1 __first1,
98       _Sent1 __last1,
99       _Iter2 __first2,
100       _Sent2 __last2,
101       _Pred& __pred,
102       _Proj1& __proj1,
103       _Proj2& __proj2,
104       _Offset __offset) {
105     if constexpr (std::bidirectional_iterator<_Sent1> && std::bidirectional_iterator<_Sent2> &&
106                   !std::random_access_iterator<_Sent1> && !std::random_access_iterator<_Sent2>) {
107       return __ends_with_fn_impl_bidirectional(
108           std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
109 
110     } else {
111       ranges::advance(__first1, __offset);
112       return ranges::equal(
113           std::move(__first1),
114           std::move(__last1),
115           std::move(__first2),
116           std::move(__last2),
117           std::ref(__pred),
118           std::ref(__proj1),
119           std::ref(__proj2));
120     }
121   }
122 
123   template <input_iterator _Iter1,
124             sentinel_for<_Iter1> _Sent1,
125             input_iterator _Iter2,
126             sentinel_for<_Iter2> _Sent2,
127             class _Pred  = ranges::equal_to,
128             class _Proj1 = identity,
129             class _Proj2 = identity>
130     requires(forward_iterator<_Iter1> || sized_sentinel_for<_Sent1, _Iter1>) &&
131             (forward_iterator<_Iter2> || sized_sentinel_for<_Sent2, _Iter2>) &&
132             indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
133   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
134       _Iter1 __first1,
135       _Sent1 __last1,
136       _Iter2 __first2,
137       _Sent2 __last2,
138       _Pred __pred   = {},
139       _Proj1 __proj1 = {},
140       _Proj2 __proj2 = {}) const {
141     return __ends_with_fn_impl(
142         std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
143   }
144 
145   template <input_range _Range1,
146             input_range _Range2,
147             class _Pred  = ranges::equal_to,
148             class _Proj1 = identity,
149             class _Proj2 = identity>
150     requires(forward_range<_Range1> || sized_range<_Range1>) && (forward_range<_Range2> || sized_range<_Range2>) &&
151             indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
152   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
153       _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
154     if constexpr (sized_range<_Range1> && sized_range<_Range2>) {
155       auto __n1 = ranges::size(__range1);
156       auto __n2 = ranges::size(__range2);
157       if (__n2 == 0)
158         return true;
159       if (__n2 > __n1)
160         return false;
161       auto __offset = __n1 - __n2;
162 
163       return __ends_with_fn_impl_with_offset(
164           ranges::begin(__range1),
165           ranges::end(__range1),
166           ranges::begin(__range2),
167           ranges::end(__range2),
168           __pred,
169           __proj1,
170           __proj2,
171           __offset);
172 
173     } else {
174       return __ends_with_fn_impl(
175           ranges::begin(__range1),
176           ranges::end(__range1),
177           ranges::begin(__range2),
178           ranges::end(__range2),
179           __pred,
180           __proj1,
181           __proj2);
182     }
183   }
184 };
185 } // namespace __ends_with
186 
187 inline namespace __cpo {
188 inline constexpr auto ends_with = __ends_with::__fn{};
189 } // namespace __cpo
190 } // namespace ranges
191 
192 _LIBCPP_END_NAMESPACE_STD
193 
194 #endif // _LIBCPP_STD_VER >= 23
195 
196 #endif // _LIBCPP___ALGORITHM_RANGES_ENDS_WITH_H
197