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_FIND_FIRST_OF_H
10 #define _LIBCPP___ALGORITHM_RANGES_FIND_FIRST_OF_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/indirectly_comparable.h>
18 #include <__ranges/access.h>
19 #include <__ranges/concepts.h>
20 #include <__ranges/dangling.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 >= 20
28 
29 _LIBCPP_BEGIN_NAMESPACE_STD
30 
31 namespace ranges {
32 namespace __find_first_of {
33 struct __fn {
34   template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
35   _LIBCPP_HIDE_FROM_ABI constexpr static _Iter1 __find_first_of_impl(
36       _Iter1 __first1,
37       _Sent1 __last1,
38       _Iter2 __first2,
39       _Sent2 __last2,
40       _Pred& __pred,
41       _Proj1& __proj1,
42       _Proj2& __proj2) {
43     for (; __first1 != __last1; ++__first1) {
44       for (auto __j = __first2; __j != __last2; ++__j) {
45         if (std::invoke(__pred, std::invoke(__proj1, *__first1), std::invoke(__proj2, *__j)))
46           return __first1;
47       }
48     }
49     return __first1;
50   }
51 
52   template <input_iterator _Iter1,
53             sentinel_for<_Iter1> _Sent1,
54             forward_iterator _Iter2,
55             sentinel_for<_Iter2> _Sent2,
56             class _Pred  = ranges::equal_to,
57             class _Proj1 = identity,
58             class _Proj2 = identity>
59     requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
60   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr _Iter1 operator()(
61       _Iter1 __first1,
62       _Sent1 __last1,
63       _Iter2 __first2,
64       _Sent2 __last2,
65       _Pred __pred   = {},
66       _Proj1 __proj1 = {},
67       _Proj2 __proj2 = {}) const {
68     return __find_first_of_impl(
69         std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
70   }
71 
72   template <input_range _Range1,
73             forward_range _Range2,
74             class _Pred  = ranges::equal_to,
75             class _Proj1 = identity,
76             class _Proj2 = identity>
77     requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
78   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range1> operator()(
79       _Range1&& __range1, _Range2&& __range2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
80     return __find_first_of_impl(
81         ranges::begin(__range1),
82         ranges::end(__range1),
83         ranges::begin(__range2),
84         ranges::end(__range2),
85         __pred,
86         __proj1,
87         __proj2);
88   }
89 };
90 } // namespace __find_first_of
91 
92 inline namespace __cpo {
93 inline constexpr auto find_first_of = __find_first_of::__fn{};
94 } // namespace __cpo
95 } // namespace ranges
96 
97 _LIBCPP_END_NAMESPACE_STD
98 
99 #endif // _LIBCPP_STD_VER >= 20
100 
101 #endif // _LIBCPP___ALGORITHM_RANGES_FIND_FIRST_OF_H
102