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_SET_DIFFERENCE_H
10 #define _LIBCPP___ALGORITHM_RANGES_SET_DIFFERENCE_H
11 
12 #include <__algorithm/in_out_result.h>
13 #include <__algorithm/make_projected.h>
14 #include <__algorithm/set_difference.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/mergeable.h>
21 #include <__ranges/access.h>
22 #include <__ranges/concepts.h>
23 #include <__ranges/dangling.h>
24 #include <__type_traits/decay.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 > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
32 
33 _LIBCPP_BEGIN_NAMESPACE_STD
34 
35 namespace ranges {
36 
37 template <class _InIter, class _OutIter>
38 using set_difference_result = in_out_result<_InIter, _OutIter>;
39 
40 namespace __set_difference {
41 
42 struct __fn {
43   template <
44       input_iterator _InIter1,
45       sentinel_for<_InIter1> _Sent1,
46       input_iterator _InIter2,
47       sentinel_for<_InIter2> _Sent2,
48       weakly_incrementable _OutIter,
49       class _Comp  = less,
50       class _Proj1 = identity,
51       class _Proj2 = identity>
52     requires mergeable<_InIter1, _InIter2, _OutIter, _Comp, _Proj1, _Proj2>
53   _LIBCPP_HIDE_FROM_ABI constexpr set_difference_result<_InIter1, _OutIter> operator()(
54       _InIter1 __first1,
55       _Sent1 __last1,
56       _InIter2 __first2,
57       _Sent2 __last2,
58       _OutIter __result,
59       _Comp __comp   = {},
60       _Proj1 __proj1 = {},
61       _Proj2 __proj2 = {}) const {
62     auto __ret = std::__set_difference(
63         __first1, __last1, __first2, __last2, __result, ranges::__make_projected_comp(__comp, __proj1, __proj2));
64     return {std::move(__ret.first), std::move(__ret.second)};
65   }
66 
67   template <
68       input_range _Range1,
69       input_range _Range2,
70       weakly_incrementable _OutIter,
71       class _Comp  = less,
72       class _Proj1 = identity,
73       class _Proj2 = identity>
74     requires mergeable<iterator_t<_Range1>, iterator_t<_Range2>, _OutIter, _Comp, _Proj1, _Proj2>
75   _LIBCPP_HIDE_FROM_ABI constexpr set_difference_result<borrowed_iterator_t<_Range1>, _OutIter>
76     operator()(
77         _Range1&& __range1,
78         _Range2&& __range2,
79         _OutIter __result,
80         _Comp __comp   = {},
81         _Proj1 __proj1 = {},
82         _Proj2 __proj2 = {}) const {
83     auto __ret = std::__set_difference(
84         ranges::begin(__range1),
85         ranges::end(__range1),
86         ranges::begin(__range2),
87         ranges::end(__range2),
88         __result,
89         ranges::__make_projected_comp(__comp, __proj1, __proj2));
90     return {std::move(__ret.first), std::move(__ret.second)};
91   }
92 };
93 
94 } // namespace __set_difference
95 
96 inline namespace __cpo {
97   inline constexpr auto set_difference = __set_difference::__fn{};
98 } // namespace __cpo
99 } // namespace ranges
100 
101 _LIBCPP_END_NAMESPACE_STD
102 
103 #endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
104 #endif // _LIBCPP___ALGORITHM_RANGES_SET_DIFFERENCE_H
105