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Diffstat (limited to 'contrib/libstdc++/include/bits/stl_iterator_base_funcs.h')
| -rw-r--r-- | contrib/libstdc++/include/bits/stl_iterator_base_funcs.h | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/contrib/libstdc++/include/bits/stl_iterator_base_funcs.h b/contrib/libstdc++/include/bits/stl_iterator_base_funcs.h new file mode 100644 index 0000000..8389f5e --- /dev/null +++ b/contrib/libstdc++/include/bits/stl_iterator_base_funcs.h @@ -0,0 +1,179 @@ +// Functions used by iterators -*- C++ -*- + +// Copyright (C) 2001, 2002 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. + * + * This file contains all of the general iterator-related utility + * functions, such as distance() and advance(). + */ + +#ifndef __GLIBCPP_INTERNAL_ITERATOR_BASE_FUNCS_H +#define __GLIBCPP_INTERNAL_ITERATOR_BASE_FUNCS_H + +#pragma GCC system_header +#include <bits/concept_check.h> + +// Since this entire file is within namespace std, there's no reason to +// waste two spaces along the left column. Thus the leading indentation is +// slightly violated from here on. +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; + } + +/** + * @brief A generalization of pointer arithmetic. + * @param first An input iterator. + * @param last An input iterator. + * @return The distance between them. + * + * Returns @c n such that first + n == last. This requires that @p last + * must be reachable from @p first. Note that @c n may be negative. + * + * For random access iterators, this uses their @c + and @c - operations + * and are constant time. For other %iterator classes they are linear time. +*/ +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; + } + +/** + * @brief A generalization of pointer arithmetic. + * @param i An input iterator. + * @param n The "delta" by which to change @p i. + * @return Nothing. + * + * This increments @p i by @p n. For bidirectional and random access + * iterators, @p n may be negative, in which case @p i is decremented. + * + * For random access iterators, this uses their @c + and @c - operations + * and are constant time. For other %iterator classes they are linear time. +*/ +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 */ + + +// Local Variables: +// mode:C++ +// End: |
