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_IF_H 10#define _LIBCPP___ALGORITHM_RANGES_COUNT_IF_H 11 12#include <__config> 13#include <__functional/identity.h> 14#include <__functional/invoke.h> 15#include <__functional/ranges_operations.h> 16#include <__iterator/concepts.h> 17#include <__iterator/incrementable_traits.h> 18#include <__iterator/iterator_traits.h> 19#include <__iterator/projected.h> 20#include <__ranges/access.h> 21#include <__ranges/concepts.h> 22#include <__utility/move.h> 23 24#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 25# pragma GCC system_header 26#endif 27 28_LIBCPP_PUSH_MACROS 29#include <__undef_macros> 30 31#if _LIBCPP_STD_VER >= 20 32 33_LIBCPP_BEGIN_NAMESPACE_STD 34 35namespace ranges { 36template <class _Iter, class _Sent, class _Proj, class _Pred> 37_LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter> 38__count_if_impl(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) { 39 iter_difference_t<_Iter> __counter(0); 40 for (; __first != __last; ++__first) { 41 if (std::invoke(__pred, std::invoke(__proj, *__first))) 42 ++__counter; 43 } 44 return __counter; 45} 46 47namespace __count_if { 48struct __fn { 49 template <input_iterator _Iter, 50 sentinel_for<_Iter> _Sent, 51 class _Proj = identity, 52 indirect_unary_predicate<projected<_Iter, _Proj>> _Predicate> 53 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter> 54 operator()(_Iter __first, _Sent __last, _Predicate __pred, _Proj __proj = {}) const { 55 return ranges::__count_if_impl(std::move(__first), std::move(__last), __pred, __proj); 56 } 57 58 template <input_range _Range, 59 class _Proj = identity, 60 indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Predicate> 61 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr range_difference_t<_Range> 62 operator()(_Range&& __r, _Predicate __pred, _Proj __proj = {}) const { 63 return ranges::__count_if_impl(ranges::begin(__r), ranges::end(__r), __pred, __proj); 64 } 65}; 66} // namespace __count_if 67 68inline namespace __cpo { 69inline constexpr auto count_if = __count_if::__fn{}; 70} // namespace __cpo 71} // namespace ranges 72 73_LIBCPP_END_NAMESPACE_STD 74 75#endif // _LIBCPP_STD_VER >= 20 76 77_LIBCPP_POP_MACROS 78 79#endif // _LIBCPP___ALGORITHM_RANGES_COUNT_IF_H 80