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/ranges_count_if.h> 13 #include <__config> 14 #include <__functional/identity.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 #if _LIBCPP_STD_VER >= 20 29 30 _LIBCPP_BEGIN_NAMESPACE_STD 31 32 namespace ranges { 33 namespace __count { 34 struct __fn { 35 template <input_iterator _Iter, sentinel_for<_Iter> _Sent, class _Type, class _Proj = identity> 36 requires indirect_binary_predicate<ranges::equal_to, projected<_Iter, _Proj>, const _Type*> 37 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter> 38 operator()(_Iter __first, _Sent __last, const _Type& __value, _Proj __proj = {}) const { 39 auto __pred = [&](auto&& __e) { return __e == __value; }; 40 return ranges::__count_if_impl(std::move(__first), std::move(__last), __pred, __proj); 41 } 42 43 template <input_range _Range, class _Type, class _Proj = identity> 44 requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<_Range>, _Proj>, const _Type*> 45 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr range_difference_t<_Range> 46 operator()(_Range&& __r, const _Type& __value, _Proj __proj = {}) const { 47 auto __pred = [&](auto&& __e) { return __e == __value; }; 48 return ranges::__count_if_impl(ranges::begin(__r), ranges::end(__r), __pred, __proj); 49 } 50 }; 51 } // namespace __count 52 53 inline namespace __cpo { 54 inline constexpr auto count = __count::__fn{}; 55 } // namespace __cpo 56 } // namespace ranges 57 58 _LIBCPP_END_NAMESPACE_STD 59 60 #endif // _LIBCPP_STD_VER >= 20 61 62 #endif // _LIBCPP___ALGORITHM_RANGES_COUNT_H 63