4 * Hewlett-Packard Company
6 * Permission to use, copy, modify, distribute and sell this software
7 * and its documentation for any purpose is hereby granted without fee,
8 * provided that the above copyright notice appear in all copies and
9 * that both that copyright notice and this permission notice appear
10 * in supporting documentation. Hewlett-Packard Company makes no
11 * representations about the suitability of this software for any
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 */