Files
clang-p2996/libcxx/include/__iterator/next.h
Nikolas Klauser 80643d9366 [libc++][NFC] Rename iterator category checks to make it obvious that they check //only// the iterator category
We plan to add concepts for checking that iterators actually provide what they claim to. This is to avoid people thinking that these type traits actually check the iterator requirements in more detail.

Reviewed By: ldionne, #libc

Spies: Mordante, libcxx-commits, wenlei

Differential Revision: https://reviews.llvm.org/D150801
2023-05-18 15:37:28 -07:00

85 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 <__assert>
#include <__config>
#include <__iterator/advance.h>
#include <__iterator/concepts.h>
#include <__iterator/incrementable_traits.h>
#include <__iterator/iterator_traits.h>
#include <__type_traits/enable_if.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _InputIter>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
typename enable_if<__has_input_iterator_category<_InputIter>::value, _InputIter>::type
next(_InputIter __x, typename iterator_traits<_InputIter>::difference_type __n = 1) {
_LIBCPP_ASSERT(__n >= 0 || __has_bidirectional_iterator_category<_InputIter>::value,
"Attempt to next(it, n) with negative n on a non-bidirectional iterator");
_VSTD::advance(__x, __n);
return __x;
}
#if _LIBCPP_STD_VER >= 20
// [range.iter.op.next]
namespace ranges {
namespace __next {
struct __fn {
template <input_or_output_iterator _Ip>
_LIBCPP_HIDE_FROM_ABI
constexpr _Ip operator()(_Ip __x) const {
++__x;
return __x;
}
template <input_or_output_iterator _Ip>
_LIBCPP_HIDE_FROM_ABI
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>
_LIBCPP_HIDE_FROM_ABI constexpr _Ip operator()(_Ip __x, _Sp __bound_sentinel) const {
ranges::advance(__x, __bound_sentinel);
return __x;
}
template <input_or_output_iterator _Ip, sentinel_for<_Ip> _Sp>
_LIBCPP_HIDE_FROM_ABI constexpr _Ip operator()(_Ip __x, iter_difference_t<_Ip> __n, _Sp __bound_sentinel) const {
ranges::advance(__x, __n, __bound_sentinel);
return __x;
}
};
} // namespace __next
inline namespace __cpo {
inline constexpr auto next = __next::__fn{};
} // namespace __cpo
} // namespace ranges
#endif // _LIBCPP_STD_VER >= 20
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___ITERATOR_NEXT_H