gcc/libstdc++-v3/include/bits/stl_iterator_base_funcs.h

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C++

// Functions used by iterators -*- C++ -*-
// Copyright (C) 2001 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING. If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
/*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996-1998
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file stl_iterator_base_funcs.h
* This is an internal header file, included by other library headers.
* You should not attempt to use it directly.
*/
#ifndef __GLIBCPP_INTERNAL_ITERATOR_BASE_FUNCS_H
#define __GLIBCPP_INTERNAL_ITERATOR_BASE_FUNCS_H
// This file contains all of the general iterator-related utility
// functions, such as distance() and advance().
// The internal file stl_iterator.h contains predefined iterators,
// such as front_insert_iterator and istream_iterator.
#pragma GCC system_header
#include <bits/concept_check.h>
namespace std
{
template<typename _InputIterator>
inline typename iterator_traits<_InputIterator>::difference_type
__distance(_InputIterator __first, _InputIterator __last, input_iterator_tag)
{
// concept requirements
__glibcpp_function_requires(_InputIteratorConcept<_InputIterator>)
typename iterator_traits<_InputIterator>::difference_type __n = 0;
while (__first != __last) {
++__first; ++__n;
}
return __n;
}
template<typename _RandomAccessIterator>
inline typename iterator_traits<_RandomAccessIterator>::difference_type
__distance(_RandomAccessIterator __first, _RandomAccessIterator __last,
random_access_iterator_tag)
{
// concept requirements
__glibcpp_function_requires(_RandomAccessIteratorConcept<_RandomAccessIterator>)
return __last - __first;
}
template<typename _InputIterator>
inline typename iterator_traits<_InputIterator>::difference_type
distance(_InputIterator __first, _InputIterator __last)
{
// concept requirements -- taken care of in __distance
return __distance(__first, __last, __iterator_category(__first));
}
template<typename _InputIter, typename _Distance>
inline void
__advance(_InputIter& __i, _Distance __n, input_iterator_tag)
{
// concept requirements
__glibcpp_function_requires(_InputIteratorConcept<_InputIter>)
while (__n--) ++__i;
}
template<typename _BidirectionalIterator, typename _Distance>
inline void
__advance(_BidirectionalIterator& __i, _Distance __n, bidirectional_iterator_tag)
{
// concept requirements
__glibcpp_function_requires(_BidirectionalIteratorConcept<_BidirectionalIterator>)
if (__n > 0)
while (__n--) ++__i;
else
while (__n++) --__i;
}
template<typename _RandomAccessIterator, typename _Distance>
inline void
__advance(_RandomAccessIterator& __i, _Distance __n, random_access_iterator_tag)
{
// concept requirements
__glibcpp_function_requires(_RandomAccessIteratorConcept<_RandomAccessIterator>)
__i += __n;
}
template<typename _InputIterator, typename _Distance>
inline void
advance(_InputIterator& __i, _Distance __n)
{
// concept requirements -- taken care of in __advance
__advance(__i, __n, __iterator_category(__i));
}
} // namespace std
#endif /* __GLIBCPP_INTERNAL_ITERATOR_BASE_FUNCS_H */
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// mode:C++
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