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_FIND_IF_H 10 #define _LIBCPP___ALGORITHM_RANGES_FIND_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/projected.h> 18 #include <__ranges/access.h> 19 #include <__ranges/concepts.h> 20 #include <__ranges/dangling.h> 21 #include <__utility/move.h> 22 23 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 24 # pragma GCC system_header 25 #endif 26 27 #if _LIBCPP_STD_VER >= 20 28 29 _LIBCPP_BEGIN_NAMESPACE_STD 30 31 namespace ranges { 32 33 template <class _Ip, class _Sp, class _Pred, class _Proj> 34 _LIBCPP_HIDE_FROM_ABI constexpr _Ip __find_if_impl(_Ip __first, _Sp __last, _Pred& __pred, _Proj& __proj) { 35 for (; __first != __last; ++__first) { 36 if (std::invoke(__pred, std::invoke(__proj, *__first))) 37 break; 38 } 39 return __first; 40 } 41 42 namespace __find_if { 43 struct __fn { 44 template <input_iterator _Ip, 45 sentinel_for<_Ip> _Sp, 46 class _Proj = identity, 47 indirect_unary_predicate<projected<_Ip, _Proj>> _Pred> 48 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr _Ip 49 operator()(_Ip __first, _Sp __last, _Pred __pred, _Proj __proj = {}) const { 50 return ranges::__find_if_impl(std::move(__first), std::move(__last), __pred, __proj); 51 } 52 53 template <input_range _Rp, class _Proj = identity, indirect_unary_predicate<projected<iterator_t<_Rp>, _Proj>> _Pred> 54 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Rp> 55 operator()(_Rp&& __r, _Pred __pred, _Proj __proj = {}) const { 56 return ranges::__find_if_impl(ranges::begin(__r), ranges::end(__r), __pred, __proj); 57 } 58 }; 59 } // namespace __find_if 60 61 inline namespace __cpo { 62 inline constexpr auto find_if = __find_if::__fn{}; 63 } // namespace __cpo 64 } // namespace ranges 65 66 _LIBCPP_END_NAMESPACE_STD 67 68 #endif // _LIBCPP_STD_VER >= 20 69 70 #endif // _LIBCPP___ALGORITHM_RANGES_FIND_IF_H 71