v1/__algorithm/ranges_count_if.h

0001 //===----------------------------------------------------------------------===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008
0009 #ifndef _LIBCPP___ALGORITHM_RANGES_COUNT_IF_H
0010 #define _LIBCPP___ALGORITHM_RANGES_COUNT_IF_H
0011
0012 #include <__algorithm/count_if.h>
0013 #include <__algorithm/iterator_operations.h>
0014 #include <__config>
0015 #include <__functional/identity.h>
0016 #include <__functional/ranges_operations.h>
0017 #include <__iterator/concepts.h>
0018 #include <__iterator/incrementable_traits.h>
0019 #include <__iterator/iterator_traits.h>
0020 #include <__iterator/projected.h>
0021 #include <__ranges/access.h>
0022 #include <__ranges/concepts.h>
0023 #include <__utility/move.h>
0024
0025 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0026 #  pragma GCC system_header
0027 #endif
0028
0029 _LIBCPP_PUSH_MACROS
0030 #include <__undef_macros>
0031
0032 #if _LIBCPP_STD_VER >= 20
0033
0034 _LIBCPP_BEGIN_NAMESPACE_STD
0035
0036 namespace ranges {
0037 struct __count_if {
0038   template <input_iterator _Iter,
0039             sentinel_for<_Iter> _Sent,
0040             class _Proj = identity,
0041             indirect_unary_predicate<projected<_Iter, _Proj>> _Predicate>
0042   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter>
0043   operator()(_Iter __first, _Sent __last, _Predicate __pred, _Proj __proj = {}) const {
0044     return std::__count_if<_RangeAlgPolicy>(std::move(__first), std::move(__last), __pred, __proj);
0045   }
0046
0047   template <input_range _Range,
0048             class _Proj = identity,
0049             indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Predicate>
0050   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr range_difference_t<_Range>
0051   operator()(_Range&& __r, _Predicate __pred, _Proj __proj = {}) const {
0052     return std::__count_if<_RangeAlgPolicy>(ranges::begin(__r), ranges::end(__r), __pred, __proj);
0053   }
0054 };
0055
0056 inline namespace __cpo {
0057 inline constexpr auto count_if = __count_if{};
0058 } // namespace __cpo
0059 } // namespace ranges
0060
0061 _LIBCPP_END_NAMESPACE_STD
0062
0063 #endif // _LIBCPP_STD_VER >= 20
0064
0065 _LIBCPP_POP_MACROS
0066
0067 #endif // _LIBCPP___ALGORITHM_RANGES_COUNT_IF_H