xref: /freebsd/contrib/llvm-project/libcxx/include/__algorithm/ranges_partition.h (revision fcaf7f8644a9988098ac6be2165bce3ea4786e91)
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_PARTITION_H
10 #define _LIBCPP___ALGORITHM_RANGES_PARTITION_H
11 
12 #include <__algorithm/iterator_operations.h>
13 #include <__algorithm/make_projected.h>
14 #include <__algorithm/partition.h>
15 #include <__algorithm/ranges_iterator_concept.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/iterator_traits.h>
22 #include <__iterator/permutable.h>
23 #include <__iterator/projected.h>
24 #include <__ranges/access.h>
25 #include <__ranges/concepts.h>
26 #include <__ranges/subrange.h>
27 #include <__utility/forward.h>
28 #include <__utility/move.h>
29 #include <type_traits>
30 
31 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
32 #  pragma GCC system_header
33 #endif
34 
35 #if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
36 
37 _LIBCPP_BEGIN_NAMESPACE_STD
38 
39 namespace ranges {
40 namespace __partition {
41 
42 struct __fn {
43 
44   template <class _Iter, class _Sent, class _Proj, class _Pred>
45   _LIBCPP_HIDE_FROM_ABI static constexpr
46   subrange<__uncvref_t<_Iter>> __partition_fn_impl(_Iter&& __first, _Sent&& __last, _Pred&& __pred, _Proj&& __proj) {
47     auto&& __projected_pred = ranges::__make_projected_pred(__pred, __proj);
48     auto __result = std::__partition<_RangeAlgPolicy>(
49         std::move(__first), std::move(__last), __projected_pred, __iterator_concept<_Iter>());
50 
51     return {std::move(__result.first), std::move(__result.second)};
52   }
53 
54   template <permutable _Iter, sentinel_for<_Iter> _Sent, class _Proj = identity,
55             indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
56   _LIBCPP_HIDE_FROM_ABI constexpr
57   subrange<_Iter> operator()(_Iter __first, _Sent __last, _Pred __pred, _Proj __proj = {}) const {
58     return __partition_fn_impl(__first, __last, __pred, __proj);
59   }
60 
61   template <forward_range _Range, class _Proj = identity,
62             indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
63   requires permutable<iterator_t<_Range>>
64   _LIBCPP_HIDE_FROM_ABI constexpr
65   borrowed_subrange_t<_Range> operator()(_Range&& __range, _Pred __pred, _Proj __proj = {}) const {
66     return __partition_fn_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj);
67   }
68 
69 };
70 
71 } // namespace __partition
72 
73 inline namespace __cpo {
74   inline constexpr auto partition = __partition::__fn{};
75 } // namespace __cpo
76 } // namespace ranges
77 
78 _LIBCPP_END_NAMESPACE_STD
79 
80 #endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
81 
82 #endif // _LIBCPP___ALGORITHM_RANGES_PARTITION_H
83