1 // -*- C++ -*- 2 //===--------------------- __ranges/concepts.h ----------------------------===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 #ifndef _LIBCPP___RANGES_CONCEPTS_H 10 #define _LIBCPP___RANGES_CONCEPTS_H 11 12 #include <__config> 13 #include <__iterator/concepts.h> 14 #include <__ranges/access.h> 15 #include <__ranges/size.h> 16 #include <type_traits> 17 18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 19 #pragma GCC system_header 20 #endif 21 22 _LIBCPP_PUSH_MACROS 23 #include <__undef_macros> 24 25 _LIBCPP_BEGIN_NAMESPACE_STD 26 27 // clang-format off 28 29 #if !defined(_LIBCPP_HAS_NO_RANGES) 30 31 namespace ranges { 32 // [range.range] 33 template <class _Tp> requires(_Tp & __t)34 concept range = requires(_Tp& __t) { 35 ranges::begin(__t); // sometimes equality-preserving 36 ranges::end(__t); 37 }; 38 39 template<class _Range> 40 concept borrowed_range = range<_Range> && 41 (is_lvalue_reference_v<_Range> || enable_borrowed_range<remove_cvref_t<_Range>>); 42 43 // `iterator_t` defined in <__ranges/access.h> 44 45 template <range _Rp> 46 using sentinel_t = decltype(ranges::end(declval<_Rp&>())); 47 48 template <range _Rp> 49 using range_difference_t = iter_difference_t<iterator_t<_Rp> >; 50 51 template <range _Rp> 52 using range_value_t = iter_value_t<iterator_t<_Rp> >; 53 54 template <range _Rp> 55 using range_reference_t = iter_reference_t<iterator_t<_Rp> >; 56 57 template <range _Rp> 58 using range_rvalue_reference_t = iter_rvalue_reference_t<iterator_t<_Rp> >; 59 60 // [range.sized] 61 template <class _Tp> requires(_Tp & __t)62 concept sized_range = range<_Tp> && requires(_Tp& __t) { ranges::size(__t); }; 63 64 // `disable_sized_range` defined in `<__ranges/size.h>` 65 66 // [range.refinements], other range refinements 67 template <class _Tp> 68 concept input_range = range<_Tp> && input_iterator<iterator_t<_Tp> >; 69 70 template <class _Tp> 71 concept forward_range = input_range<_Tp> && forward_iterator<iterator_t<_Tp> >; 72 73 template <class _Tp> 74 concept bidirectional_range = forward_range<_Tp> && bidirectional_iterator<iterator_t<_Tp> >; 75 76 template <class _Tp> 77 concept random_access_range = 78 bidirectional_range<_Tp> && random_access_iterator<iterator_t<_Tp> >; 79 80 template <class _Tp> 81 concept common_range = range<_Tp> && same_as<iterator_t<_Tp>, sentinel_t<_Tp> >; 82 } // namespace ranges 83 84 #endif // !defined(_LIBCPP_HAS_NO_RANGES) 85 86 // clang-format on 87 88 _LIBCPP_END_NAMESPACE_STD 89 90 _LIBCPP_POP_MACROS 91 92 #endif // _LIBCPP___RANGES_CONCEPTS_H 93