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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-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___CXX03___ITERATOR_NEXT_H11#define _LIBCPP___CXX03___ITERATOR_NEXT_H12 13#include <__cxx03/__assert>14#include <__cxx03/__config>15#include <__cxx03/__iterator/advance.h>16#include <__cxx03/__iterator/iterator_traits.h>17#include <__cxx03/__type_traits/enable_if.h>18 19#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)20# pragma GCC system_header21#endif22 23_LIBCPP_BEGIN_NAMESPACE_STD24 25template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> = 0>26inline _LIBCPP_HIDE_FROM_ABI _InputIter27next(_InputIter __x, typename iterator_traits<_InputIter>::difference_type __n = 1) {28 // Calling `advance` with a negative value on a non-bidirectional iterator is a no-op in the current implementation.29 // Note that this check duplicates the similar check in `std::advance`.30 _LIBCPP_ASSERT_PEDANTIC(__n >= 0 || __has_bidirectional_iterator_category<_InputIter>::value,31 "Attempt to next(it, n) with negative n on a non-bidirectional iterator");32 33 std::advance(__x, __n);34 return __x;35}36 37_LIBCPP_END_NAMESPACE_STD38 39#endif // _LIBCPP___CXX03___ITERATOR_NEXT_H40