xref: /llvm-project/libcxx/include/__algorithm/ranges_mismatch.h (revision d10dc5a06fac4dcabf2264c64c8672c6f6ae36fb)
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_MISMATCH_H
10 #define _LIBCPP___ALGORITHM_RANGES_MISMATCH_H
11 
12 #include <__algorithm/in_in_result.h>
13 #include <__algorithm/mismatch.h>
14 #include <__algorithm/unwrap_range.h>
15 #include <__config>
16 #include <__functional/identity.h>
17 #include <__functional/invoke.h>
18 #include <__functional/ranges_operations.h>
19 #include <__iterator/concepts.h>
20 #include <__iterator/indirectly_comparable.h>
21 #include <__ranges/access.h>
22 #include <__ranges/concepts.h>
23 #include <__ranges/dangling.h>
24 #include <__utility/move.h>
25 
26 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
27 #  pragma GCC system_header
28 #endif
29 
30 _LIBCPP_PUSH_MACROS
31 #include <__undef_macros>
32 
33 _LIBCPP_BEGIN_NAMESPACE_STD
34 
35 #if _LIBCPP_STD_VER >= 20
36 
37 namespace ranges {
38 
39 template <class _I1, class _I2>
40 using mismatch_result = in_in_result<_I1, _I2>;
41 
42 struct __mismatch {
43   template <class _I1, class _S1, class _I2, class _S2, class _Pred, class _Proj1, class _Proj2>
44   static _LIBCPP_HIDE_FROM_ABI constexpr mismatch_result<_I1, _I2>
45   __go(_I1 __first1, _S1 __last1, _I2 __first2, _S2 __last2, _Pred& __pred, _Proj1& __proj1, _Proj2& __proj2) {
46     if constexpr (forward_iterator<_I1> && forward_iterator<_I2>) {
47       auto __range1 = std::__unwrap_range(__first1, __last1);
48       auto __range2 = std::__unwrap_range(__first2, __last2);
49       auto __res =
50           std::__mismatch(__range1.first, __range1.second, __range2.first, __range2.second, __pred, __proj1, __proj2);
51       return {std::__rewrap_range<_S1>(__first1, __res.first), std::__rewrap_range<_S2>(__first2, __res.second)};
52     } else {
53       auto __res = std::__mismatch(
54           std::move(__first1), std::move(__last1), std::move(__first2), std::move(__last2), __pred, __proj1, __proj2);
55       return {std::move(__res.first), std::move(__res.second)};
56     }
57   }
58 
59   template <input_iterator _I1,
60             sentinel_for<_I1> _S1,
61             input_iterator _I2,
62             sentinel_for<_I2> _S2,
63             class _Pred  = ranges::equal_to,
64             class _Proj1 = identity,
65             class _Proj2 = identity>
66     requires indirectly_comparable<_I1, _I2, _Pred, _Proj1, _Proj2>
67   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr mismatch_result<_I1, _I2> operator()(
68       _I1 __first1, _S1 __last1, _I2 __first2, _S2 __last2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {})
69       const {
70     return __go(std::move(__first1), __last1, std::move(__first2), __last2, __pred, __proj1, __proj2);
71   }
72 
73   template <input_range _R1,
74             input_range _R2,
75             class _Pred  = ranges::equal_to,
76             class _Proj1 = identity,
77             class _Proj2 = identity>
78     requires indirectly_comparable<iterator_t<_R1>, iterator_t<_R2>, _Pred, _Proj1, _Proj2>
79   [[nodiscard]]
80   _LIBCPP_HIDE_FROM_ABI constexpr mismatch_result<borrowed_iterator_t<_R1>, borrowed_iterator_t<_R2>>
81   operator()(_R1&& __r1, _R2&& __r2, _Pred __pred = {}, _Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const {
82     return __go(
83         ranges::begin(__r1), ranges::end(__r1), ranges::begin(__r2), ranges::end(__r2), __pred, __proj1, __proj2);
84   }
85 };
86 
87 inline namespace __cpo {
88 constexpr inline auto mismatch = __mismatch{};
89 } // namespace __cpo
90 } // namespace ranges
91 
92 #endif // _LIBCPP_STD_VER >= 20
93 
94 _LIBCPP_END_NAMESPACE_STD
95 
96 _LIBCPP_POP_MACROS
97 
98 #endif // _LIBCPP___ALGORITHM_RANGES_MISMATCH_H
99