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_STARTS_WITH_H
10 #define _LIBCPP___ALGORITHM_RANGES_STARTS_WITH_H
11 
12 #include <__algorithm/in_in_result.h>
13 #include <__algorithm/ranges_mismatch.h>
14 #include <__config>
15 #include <__functional/identity.h>
16 #include <__functional/ranges_operations.h>
17 #include <__iterator/concepts.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 >= 23
28 
29 _LIBCPP_BEGIN_NAMESPACE_STD
30 
31 namespace ranges {
32 namespace __starts_with {
33 struct __fn {
34   template <input_iterator _Iter1,
35             sentinel_for<_Iter1> _Sent1,
36             input_iterator _Iter2,
37             sentinel_for<_Iter2> _Sent2,
38             class _Pred  = ranges::equal_to,
39             class _Proj1 = identity,
40             class _Proj2 = identity>
41     requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
42   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
43       _Iter1 __first1,
44       _Sent1 __last1,
45       _Iter2 __first2,
46       _Sent2 __last2,
47       _Pred __pred   = {},
48       _Proj1 __proj1 = {},
49       _Proj2 __proj2 = {}) const {
50     return __mismatch::__fn::__go(
51                std::move(__first1),
52                std::move(__last1),
53                std::move(__first2),
54                std::move(__last2),
55                __pred,
56                __proj1,
57                __proj2)
58                .in2 == __last2;
59   }
60 
61   template <input_range _Range1,
62             input_range _Range2,
63             class _Pred  = ranges::equal_to,
64             class _Proj1 = identity,
65             class _Proj2 = identity>
66     requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
67   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(
68       _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
69     return __mismatch::__fn::__go(
70                ranges::begin(__range1),
71                ranges::end(__range1),
72                ranges::begin(__range2),
73                ranges::end(__range2),
74                __pred,
75                __proj1,
76                __proj2)
77                .in2 == ranges::end(__range2);
78   }
79 };
80 } // namespace __starts_with
81 inline namespace __cpo {
82 inline constexpr auto starts_with = __starts_with::__fn{};
83 } // namespace __cpo
84 } // namespace ranges
85 
86 _LIBCPP_END_NAMESPACE_STD
87 
88 #endif // _LIBCPP_STD_VER >= 23
89 
90 #endif // _LIBCPP___ALGORITHM_RANGES_STARTS_WITH_H
91