Files
clang-p2996/libcxx/include/__iterator/next.h
Christopher Di Bella 332da1c283 [libcxx][iwyu] ensures we IWYU as prep for modules
This has been broken out of D104170 since it should be merged whether or
not we go ahead with the module map changes.

Differential Revision: https://reviews.llvm.org/D104175
2021-06-15 19:43:25 +00:00

83 lines
2.4 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___ITERATOR_NEXT_H
#define _LIBCPP___ITERATOR_NEXT_H
#include <__config>
#include <__debug>
#include <__function_like.h>
#include <__iterator/advance.h>
#include <__iterator/concepts.h>
#include <__iterator/incrementable_traits.h>
#include <__iterator/iterator_traits.h>
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _InputIter>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
typename enable_if<__is_cpp17_input_iterator<_InputIter>::value, _InputIter>::type
next(_InputIter __x, typename iterator_traits<_InputIter>::difference_type __n = 1) {
_LIBCPP_ASSERT(__n >= 0 || __is_cpp17_bidirectional_iterator<_InputIter>::value,
"Attempt to next(it, n) with negative n on a non-bidirectional iterator");
_VSTD::advance(__x, __n);
return __x;
}
#if !defined(_LIBCPP_HAS_NO_RANGES)
namespace ranges {
struct __next_fn final : private __function_like {
constexpr explicit __next_fn(__tag __x) noexcept : __function_like(__x) {}
template <input_or_output_iterator _Ip>
constexpr _Ip operator()(_Ip __x) const {
++__x;
return __x;
}
template <input_or_output_iterator _Ip>
constexpr _Ip operator()(_Ip __x, iter_difference_t<_Ip> __n) const {
ranges::advance(__x, __n);
return __x;
}
template <input_or_output_iterator _Ip, sentinel_for<_Ip> _Sp>
constexpr _Ip operator()(_Ip __x, _Sp __bound) const {
ranges::advance(__x, __bound);
return __x;
}
template <input_or_output_iterator _Ip, sentinel_for<_Ip> _Sp>
constexpr _Ip operator()(_Ip __x, iter_difference_t<_Ip> __n, _Sp __bound) const {
ranges::advance(__x, __n, __bound);
return __x;
}
};
inline constexpr auto next = __next_fn(__function_like::__tag());
} // namespace ranges
#endif // !defined(_LIBCPP_HAS_NO_RANGES)
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP___ITERATOR_PRIMITIVES_H