1 // -*- C++ -*- 2 //===----------------------------------------------------------------------===// 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___ITERATOR_PROJECTED_H 10 #define _LIBCPP___ITERATOR_PROJECTED_H 11 12 #include <__config> 13 #include <__iterator/concepts.h> 14 #include <__iterator/incrementable_traits.h> 15 #include <type_traits> 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 _LIBCPP_BEGIN_NAMESPACE_STD 25 26 #if !defined(_LIBCPP_HAS_NO_RANGES) 27 28 template<indirectly_readable _It, indirectly_regular_unary_invocable<_It> _Proj> 29 struct projected { 30 using value_type = remove_cvref_t<indirect_result_t<_Proj&, _It>>; 31 indirect_result_t<_Proj&, _It> operator*() const; // not defined 32 }; 33 34 template<weakly_incrementable _It, class _Proj> 35 struct incrementable_traits<projected<_It, _Proj>> { 36 using difference_type = iter_difference_t<_It>; 37 }; 38 39 #endif // !defined(_LIBCPP_HAS_NO_RANGES) 40 41 _LIBCPP_END_NAMESPACE_STD 42 43 _LIBCPP_POP_MACROS 44 45 #endif // _LIBCPP___ITERATOR_PROJECTED_H 46