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_ADJACENT_FIND_H 10 #define _LIBCPP___ALGORITHM_RANGES_ADJACENT_FIND_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 _LIBCPP_PUSH_MACROS 28 #include <__undef_macros> 29 30 #if _LIBCPP_STD_VER >= 20 31 32 _LIBCPP_BEGIN_NAMESPACE_STD 33 34 namespace ranges { 35 struct __adjacent_find { 36 template <class _Iter, class _Sent, class _Proj, class _Pred> 37 _LIBCPP_HIDE_FROM_ABI constexpr static _Iter 38 __adjacent_find_impl(_Iter __first, _Sent __last, _Pred& __pred, _Proj& __proj) { 39 if (__first == __last) 40 return __first; 41 42 auto __i = __first; 43 while (++__i != __last) { 44 if (std::invoke(__pred, std::invoke(__proj, *__first), std::invoke(__proj, *__i))) 45 return __first; 46 __first = __i; 47 } 48 return __i; 49 } 50 51 template <forward_iterator _Iter, 52 sentinel_for<_Iter> _Sent, 53 class _Proj = identity, 54 indirect_binary_predicate<projected<_Iter, _Proj>, projected<_Iter, _Proj>> _Pred = ranges::equal_to> 55 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _Iter 56 operator()(_Iter __first, _Sent __last, _Pred __pred = {}, _Proj __proj = {}) const { 57 return __adjacent_find_impl(std::move(__first), std::move(__last), __pred, __proj); 58 } 59 60 template <forward_range _Range, 61 class _Proj = identity, 62 indirect_binary_predicate<projected<iterator_t<_Range>, _Proj>, projected<iterator_t<_Range>, _Proj>> 63 _Pred = ranges::equal_to> 64 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr borrowed_iterator_t<_Range> 65 operator()(_Range&& __range, _Pred __pred = {}, _Proj __proj = {}) const { 66 return __adjacent_find_impl(ranges::begin(__range), ranges::end(__range), __pred, __proj); 67 } 68 }; 69 70 inline namespace __cpo { 71 inline constexpr auto adjacent_find = __adjacent_find{}; 72 } // namespace __cpo 73 } // namespace ranges 74 75 _LIBCPP_END_NAMESPACE_STD 76 77 #endif // _LIBCPP_STD_VER >= 20 78 79 _LIBCPP_POP_MACROS 80 81 #endif // _LIBCPP___ALGORITHM_RANGES_ADJACENT_FIND_H 82