xref: /freebsd/contrib/llvm-project/libcxx/include/__algorithm/ranges_count.h (revision 9bc300465e48e19d794d88d0c158a2adb92c7197)
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_COUNT_H
10 #define _LIBCPP___ALGORITHM_RANGES_COUNT_H
11 
12 #include <__algorithm/count.h>
13 #include <__algorithm/iterator_operations.h>
14 #include <__config>
15 #include <__functional/identity.h>
16 #include <__functional/ranges_operations.h>
17 #include <__iterator/concepts.h>
18 #include <__iterator/incrementable_traits.h>
19 #include <__iterator/iterator_traits.h>
20 #include <__iterator/projected.h>
21 #include <__ranges/access.h>
22 #include <__ranges/concepts.h>
23 #include <__utility/move.h>
24 
25 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
26 #  pragma GCC system_header
27 #endif
28 
29 _LIBCPP_PUSH_MACROS
30 #include <__undef_macros>
31 
32 #if _LIBCPP_STD_VER >= 20
33 
34 _LIBCPP_BEGIN_NAMESPACE_STD
35 
36 namespace ranges {
37 namespace __count {
38 struct __fn {
39   template <input_iterator _Iter, sentinel_for<_Iter> _Sent, class _Type, class _Proj = identity>
40     requires indirect_binary_predicate<ranges::equal_to, projected<_Iter, _Proj>, const _Type*>
41   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter>
42   operator()(_Iter __first, _Sent __last, const _Type& __value, _Proj __proj = {}) const {
43     return std::__count<_RangeAlgPolicy>(std::move(__first), std::move(__last), __value, __proj);
44   }
45 
46   template <input_range _Range, class _Type, class _Proj = identity>
47     requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Range>, _Proj>, const _Type*>
48   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr range_difference_t<_Range>
49   operator()(_Range&& __r, const _Type& __value, _Proj __proj = {}) const {
50     return std::__count<_RangeAlgPolicy>(ranges::begin(__r), ranges::end(__r), __value, __proj);
51   }
52 };
53 } // namespace __count
54 
55 inline namespace __cpo {
56 inline constexpr auto count = __count::__fn{};
57 } // namespace __cpo
58 } // namespace ranges
59 
60 _LIBCPP_END_NAMESPACE_STD
61 
62 #endif // _LIBCPP_STD_VER >= 20
63 
64 _LIBCPP_POP_MACROS
65 
66 #endif // _LIBCPP___ALGORITHM_RANGES_COUNT_H
67