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_ITERATOR_CONCEPT_H 10 #define _LIBCPP___ALGORITHM_RANGES_ITERATOR_CONCEPT_H 11 12 #include <__config> 13 #include <__iterator/concepts.h> 14 #include <__iterator/iterator_traits.h> 15 #include <__type_traits/remove_cvref.h> 16 17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 18 # pragma GCC system_header 19 #endif 20 21 _LIBCPP_PUSH_MACROS 22 #include <__undef_macros> 23 24 #if _LIBCPP_STD_VER >= 20 25 26 _LIBCPP_BEGIN_NAMESPACE_STD 27 28 namespace ranges { 29 30 template <class _IterMaybeQualified> 31 consteval auto __get_iterator_concept() { 32 using _Iter = __remove_cvref_t<_IterMaybeQualified>; 33 34 if constexpr (contiguous_iterator<_Iter>) 35 return contiguous_iterator_tag(); 36 else if constexpr (random_access_iterator<_Iter>) 37 return random_access_iterator_tag(); 38 else if constexpr (bidirectional_iterator<_Iter>) 39 return bidirectional_iterator_tag(); 40 else if constexpr (forward_iterator<_Iter>) 41 return forward_iterator_tag(); 42 else if constexpr (input_iterator<_Iter>) 43 return input_iterator_tag(); 44 } 45 46 template <class _Iter> 47 using __iterator_concept = decltype(__get_iterator_concept<_Iter>()); 48 49 } // namespace ranges 50 _LIBCPP_END_NAMESPACE_STD 51 52 #endif // _LIBCPP_STD_VER >= 20 53 54 _LIBCPP_POP_MACROS 55 56 #endif // _LIBCPP___ALGORITHM_RANGES_ITERATOR_CONCEPT_H 57