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 > 17
28 
29 _LIBCPP_BEGIN_NAMESPACE_STD
30 
31 namespace ranges {
32 namespace __find_first_of {
33 struct __fn {
34 
35   template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
36   _LIBCPP_HIDE_FROM_ABI constexpr static
37   _Iter1 __find_first_of_impl(_Iter1 __first1, _Sent1 __last1,
38                               _Iter2 __first2, _Sent2 __last2,
39                               _Pred& __pred,
40                               _Proj1& __proj1,
41                               _Proj2& __proj2) {
42     for (; __first1 != __last1; ++__first1) {
43       for (auto __j = __first2; __j != __last2; ++__j) {
44         if (std::invoke(__pred, std::invoke(__proj1, *__first1), std::invoke(__proj2, *__j)))
45           return __first1;
46       }
47     }
48     return __first1;
49   }
50 
51   template <input_iterator _Iter1, sentinel_for<_Iter1> _Sent1,
52             forward_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
53             class _Pred = ranges::equal_to,
54             class _Proj1 = identity,
55             class _Proj2 = identity>
56     requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
57   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr
58   _Iter1 operator()(_Iter1 __first1, _Sent1 __last1,
59                     _Iter2 __first2, _Sent2 __last2,
60                     _Pred __pred = {},
61                     _Proj1 __proj1 = {},
62                     _Proj2 __proj2 = {}) const {
63     return __find_first_of_impl(std::move(__first1), std::move(__last1),
64                                 std::move(__first2), std::move(__last2),
65                                 __pred,
66                                 __proj1,
67                                 __proj2);
68   }
69 
70   template <input_range _Range1,
71             forward_range _Range2,
72             class _Pred = ranges::equal_to,
73             class _Proj1 = identity,
74             class _Proj2 = identity>
75     requires indirectly_comparable<iterator_t<_Range1>, iterator_t<_Range2>, _Pred, _Proj1, _Proj2>
76   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr
77   borrowed_iterator_t<_Range1> operator()(_Range1&& __range1,
78                                           _Range2&& __range2,
79                                           _Pred __pred = {},
80                                           _Proj1 __proj1 = {},
81                                           _Proj2 __proj2 = {}) const {
82     return __find_first_of_impl(ranges::begin(__range1), ranges::end(__range1),
83                                 ranges::begin(__range2), ranges::end(__range2),
84                                 __pred,
85                                 __proj1,
86                                 __proj2);
87   }
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 > 17
100 
101 #endif // _LIBCPP___ALGORITHM_RANGES_FIND_FIRST_OF_H
102