5fab33af7f
Use `using` aliases to avoid instantiating lots of types Reviewed By: ldionne, #libc Spies: libcxx-commits, miyuki Differential Revision: https://reviews.llvm.org/D132785
52 lines
1.5 KiB
C++
52 lines
1.5 KiB
C++
//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef _LIBCPP___ALGORITHM_RANGES_ITERATOR_CONCEPT_H
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#define _LIBCPP___ALGORITHM_RANGES_ITERATOR_CONCEPT_H
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#include <__config>
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#include <__iterator/concepts.h>
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#include <__iterator/iterator_traits.h>
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#include <type_traits>
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#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
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# pragma GCC system_header
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#endif
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#if _LIBCPP_STD_VER > 17
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_LIBCPP_BEGIN_NAMESPACE_STD
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namespace ranges {
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template <class _IterMaybeQualified>
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consteval auto __get_iterator_concept() {
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using _Iter = __remove_cvref_t<_IterMaybeQualified>;
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if constexpr (contiguous_iterator<_Iter>)
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return contiguous_iterator_tag();
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else if constexpr (random_access_iterator<_Iter>)
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return random_access_iterator_tag();
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else if constexpr (bidirectional_iterator<_Iter>)
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return bidirectional_iterator_tag();
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else if constexpr (forward_iterator<_Iter>)
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return forward_iterator_tag();
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else if constexpr (input_iterator<_Iter>)
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return input_iterator_tag();
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}
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template <class _Iter>
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using __iterator_concept = decltype(__get_iterator_concept<_Iter>());
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} // namespace ranges
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_LIBCPP_END_NAMESPACE_STD
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#endif // _LIBCPP_STD_VER > 17
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#endif // _LIBCPP___ALGORITHM_RANGES_ITERATOR_CONCEPT_H
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