libstdc++
ext/iterator
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1// HP/SGI iterator extensions -*- C++ -*-
2
3// Copyright (C) 2001-2021 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996-1998
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
51/** @file ext/iterator
52 * This file is a GNU extension to the Standard C++ Library (possibly
53 * containing extensions from the HP/SGI STL subset).
54 */
55
56#ifndef _EXT_ITERATOR
57#define _EXT_ITERATOR 1
58
59#pragma GCC system_header
60
61#include <bits/concept_check.h>
62#include <iterator>
63
64namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
65{
66_GLIBCXX_BEGIN_NAMESPACE_VERSION
67
68 // There are two signatures for distance. In addition to the one
69 // taking two iterators and returning a result, there is another
70 // taking two iterators and a reference-to-result variable, and
71 // returning nothing. The latter seems to be an SGI extension.
72 // -- pedwards
73 template<typename _InputIterator, typename _Distance>
74 inline void
75 __distance(_InputIterator __first, _InputIterator __last,
76 _Distance& __n, std::input_iterator_tag)
77 {
78 // concept requirements
79 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
80 while (__first != __last)
81 {
82 ++__first;
83 ++__n;
84 }
85 }
86
87 template<typename _RandomAccessIterator, typename _Distance>
88 inline void
89 __distance(_RandomAccessIterator __first, _RandomAccessIterator __last,
90 _Distance& __n, std::random_access_iterator_tag)
91 {
92 // concept requirements
93 __glibcxx_function_requires(_RandomAccessIteratorConcept<
94 _RandomAccessIterator>)
95 __n += __last - __first;
96 }
97
98 /**
99 * This is an SGI extension.
100 * @ingroup SGIextensions
101 * @doctodo
102 */
103 template<typename _InputIterator, typename _Distance>
104 inline void
105 distance(_InputIterator __first, _InputIterator __last,
106 _Distance& __n)
107 {
108 // concept requirements -- taken care of in __distance
109 __distance(__first, __last, __n, std::__iterator_category(__first));
110 }
111
112_GLIBCXX_END_NAMESPACE_VERSION
113} // namespace
114
115#endif
116