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9 * that both that copyright notice and this permission notice appear
10 * in supporting documentation. Hewlett-Packard Company makes no
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12 * purpose. It is provided "as is" without express or implied warranty.
15 * Copyright (c) 1996-1998
16 * Silicon Graphics Computer Systems, Inc.
18 * Permission to use, copy, modify, distribute and sell this software
19 * and its documentation for any purpose is hereby granted without fee,
20 * provided that the above copyright notice appear in all copies and
21 * that both that copyright notice and this permission notice appear
22 * in supporting documentation. Silicon Graphics makes no
23 * representations about the suitability of this software for any
24 * purpose. It is provided "as is" without express or implied warranty.
27 /* NOTE: This is an internal header file, included by other STL headers.
28 * You should not attempt to use it directly.
31 #ifndef __SGI_STL_INTERNAL_ITERATOR_BASE_FUNCS_H
32 #define __SGI_STL_INTERNAL_ITERATOR_BASE_FUNCS_H
34 // This file contains all of the general iterator-related utility
35 // functions, such as distance() and advance().
36 // The internal file stl_iterator.h contains predefined iterators,
37 // such as front_insert_iterator and istream_iterator.
39 #pragma GCC system_header
40 #include <bits/concept_check.h>
45 // There are two signatures for distance. In addition to the one taking
46 // two iterators and returning a result, there is another taking two
47 // iterators and a reference-to-result variable, and returning nothing.
48 // The latter seems to be an SGI extension. -- pedwards
49 template <class _InputIterator, class _Distance>
50 inline void __distance(_InputIterator __first, _InputIterator __last,
51 _Distance& __n, input_iterator_tag)
53 // concept requirements
54 __glibcpp_function_requires(_InputIteratorConcept<_InputIterator>);
55 while (__first != __last) { ++__first; ++__n; }
58 template <class _RandomAccessIterator, class _Distance>
59 inline void __distance(_RandomAccessIterator __first,
60 _RandomAccessIterator __last,
61 _Distance& __n, random_access_iterator_tag)
63 // concept requirements
64 __glibcpp_function_requires(_RandomAccessIteratorConcept<_RandomAccessIterator>);
65 __n += __last - __first;
68 template <class _InputIterator, class _Distance>
69 inline void distance(_InputIterator __first,
70 _InputIterator __last, _Distance& __n)
72 // concept requirements -- taken care of in __distance
73 __distance(__first, __last, __n, iterator_category(__first));
76 template <class _InputIterator>
77 inline typename iterator_traits<_InputIterator>::difference_type
78 __distance(_InputIterator __first, _InputIterator __last, input_iterator_tag)
80 // concept requirements
81 __glibcpp_function_requires(_InputIteratorConcept<_InputIterator>);
82 typename iterator_traits<_InputIterator>::difference_type __n = 0;
83 while (__first != __last) {
89 template <class _RandomAccessIterator>
90 inline typename iterator_traits<_RandomAccessIterator>::difference_type
91 __distance(_RandomAccessIterator __first, _RandomAccessIterator __last,
92 random_access_iterator_tag)
94 // concept requirements
95 __glibcpp_function_requires(_RandomAccessIteratorConcept<_RandomAccessIterator>);
96 return __last - __first;
99 template <class _InputIterator>
100 inline typename iterator_traits<_InputIterator>::difference_type
101 distance(_InputIterator __first, _InputIterator __last)
103 // concept requirements -- taken care of in __distance
104 typedef typename iterator_traits<_InputIterator>::iterator_category
106 return __distance(__first, __last, _Category());
109 template <class _InputIter, class _Distance>
110 inline void __advance(_InputIter& __i, _Distance __n, input_iterator_tag)
112 // concept requirements
113 __glibcpp_function_requires(_InputIteratorConcept<_InputIter>);
117 template <class _BidirectionalIterator, class _Distance>
118 inline void __advance(_BidirectionalIterator& __i, _Distance __n,
119 bidirectional_iterator_tag)
121 // concept requirements
122 __glibcpp_function_requires(_BidirectionalIteratorConcept<_BidirectionalIterator>);
129 template <class _RandomAccessIterator, class _Distance>
130 inline void __advance(_RandomAccessIterator& __i, _Distance __n,
131 random_access_iterator_tag)
133 // concept requirements
134 __glibcpp_function_requires(_RandomAccessIteratorConcept<_RandomAccessIterator>);
138 template <class _InputIterator, class _Distance>
139 inline void advance(_InputIterator& __i, _Distance __n)
141 // concept requirements -- taken care of in __advance
142 __advance(__i, __n, iterator_category(__i));
147 #endif /* __SGI_STL_INTERNAL_ITERATOR_BASE_FUNCS_H */