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/iterator_operations.h>
14 #include <__algorithm/make_projected.h>
15 #include <__algorithm/set_difference.h>
16 #include <__config>
17 #include <__functional/identity.h>
18 #include <__functional/invoke.h>
19 #include <__functional/ranges_operations.h>
20 #include <__iterator/concepts.h>
21 #include <__iterator/mergeable.h>
22 #include <__ranges/access.h>
23 #include <__ranges/concepts.h>
24 #include <__ranges/dangling.h>
25 #include <__type_traits/decay.h>
26 #include <__utility/move.h>
27 #include <__utility/pair.h>
28 
29 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
30 #  pragma GCC system_header
31 #endif
32 
33 #if _LIBCPP_STD_VER >= 20
34 
35 _LIBCPP_BEGIN_NAMESPACE_STD
36 
37 namespace ranges {
38 
39 template <class _InIter, class _OutIter>
40 using set_difference_result = in_out_result<_InIter, _OutIter>;
41 
42 namespace __set_difference {
43 
44 struct __fn {
45   template <input_iterator _InIter1,
46             sentinel_for<_InIter1> _Sent1,
47             input_iterator _InIter2,
48             sentinel_for<_InIter2> _Sent2,
49             weakly_incrementable _OutIter,
50             class _Comp  = less,
51             class _Proj1 = identity,
52             class _Proj2 = identity>
53     requires mergeable<_InIter1, _InIter2, _OutIter, _Comp, _Proj1, _Proj2>
54   _LIBCPP_HIDE_FROM_ABI constexpr set_difference_result<_InIter1, _OutIter> operator()(
55       _InIter1 __first1,
56       _Sent1 __last1,
57       _InIter2 __first2,
58       _Sent2 __last2,
59       _OutIter __result,
60       _Comp __comp   = {},
61       _Proj1 __proj1 = {},
62       _Proj2 __proj2 = {}) const {
63     auto __ret = std::__set_difference<_RangeAlgPolicy>(
64         __first1, __last1, __first2, __last2, __result, ranges::__make_projected_comp(__comp, __proj1, __proj2));
65     return {std::move(__ret.first), std::move(__ret.second)};
66   }
67 
68   template <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()(_Range1&& __range1,
77              _Range2&& __range2,
78              _OutIter __result,
79              _Comp __comp   = {},
80              _Proj1 __proj1 = {},
81              _Proj2 __proj2 = {}) const {
82     auto __ret = std::__set_difference<_RangeAlgPolicy>(
83         ranges::begin(__range1),
84         ranges::end(__range1),
85         ranges::begin(__range2),
86         ranges::end(__range2),
87         __result,
88         ranges::__make_projected_comp(__comp, __proj1, __proj2));
89     return {std::move(__ret.first), std::move(__ret.second)};
90   }
91 };
92 
93 } // namespace __set_difference
94 
95 inline namespace __cpo {
96 inline constexpr auto set_difference = __set_difference::__fn{};
97 } // namespace __cpo
98 } // namespace ranges
99 
100 _LIBCPP_END_NAMESPACE_STD
101 
102 #endif // _LIBCPP_STD_VER >= 20
103 #endif // _LIBCPP___ALGORITHM_RANGES_SET_DIFFERENCE_H
104