libstdc++
iterator.h
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1 // -*- C++ -*-
2 
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16 // Under Section 7 of GPL version 3, you are granted additional
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24 
25 /** @file parallel/iterator.h
26  * @brief Helper iterator classes for the std::transform() functions.
27  * This file is a GNU parallel extension to the Standard C++ Library.
28  */
29 
30 // Written by Johannes Singler.
31 
32 #ifndef _GLIBCXX_PARALLEL_ITERATOR_H
33 #define _GLIBCXX_PARALLEL_ITERATOR_H 1
34 
36 #include <bits/stl_pair.h>
37 
38 namespace __gnu_parallel
39 {
40  /** @brief A pair of iterators. The usual iterator operations are
41  * applied to both child iterators.
42  */
43  template<typename _Iterator1, typename _Iterator2,
44  typename _IteratorCategory>
45  class _IteratorPair : public std::pair<_Iterator1, _Iterator2>
46  {
47  private:
49 
50  public:
51  typedef _IteratorCategory iterator_category;
52  typedef void value_type;
53 
55  typedef typename _TraitsType::difference_type difference_type;
56  typedef _IteratorPair* pointer;
57  typedef _IteratorPair& reference;
58 
59  _IteratorPair() { }
60 
61  _IteratorPair(const _Iterator1& __first, const _Iterator2& __second)
62  : _Base(__first, __second) { }
63 
64  // Pre-increment operator.
66  operator++()
67  {
68  ++_Base::first;
69  ++_Base::second;
70  return *this;
71  }
72 
73  // Post-increment operator.
74  const _IteratorPair
75  operator++(int)
76  { return _IteratorPair(_Base::first++, _Base::second++); }
77 
78  // Pre-decrement operator.
80  operator--()
81  {
82  --_Base::first;
83  --_Base::second;
84  return *this;
85  }
86 
87  // Post-decrement operator.
88  const _IteratorPair
89  operator--(int)
90  { return _IteratorPair(_Base::first--, _Base::second--); }
91 
92  // Type conversion.
93  operator _Iterator2() const
94  { return _Base::second; }
95 
97  operator=(const _IteratorPair& __other)
98  {
99  _Base::first = __other.first;
100  _Base::second = __other.second;
101  return *this;
102  }
103 
105  operator+(difference_type __delta) const
106  { return _IteratorPair(_Base::first + __delta, _Base::second + __delta);
107  }
108 
109  difference_type
110  operator-(const _IteratorPair& __other) const
111  { return _Base::first - __other.first; }
112  };
113 
114 
115  /** @brief A triple of iterators. The usual iterator operations are
116  applied to all three child iterators.
117  */
118  template<typename _Iterator1, typename _Iterator2, typename _Iterator3,
119  typename _IteratorCategory>
121  {
122  public:
123  typedef _IteratorCategory iterator_category;
124  typedef void value_type;
126  difference_type;
127  typedef _IteratorTriple* pointer;
128  typedef _IteratorTriple& reference;
129 
130  _Iterator1 _M_first;
131  _Iterator2 _M_second;
132  _Iterator3 _M_third;
133 
134  _IteratorTriple() { }
135 
136  _IteratorTriple(const _Iterator1& __first, const _Iterator2& __second,
137  const _Iterator3& __third)
138  {
139  _M_first = __first;
140  _M_second = __second;
141  _M_third = __third;
142  }
143 
144  // Pre-increment operator.
146  operator++()
147  {
148  ++_M_first;
149  ++_M_second;
150  ++_M_third;
151  return *this;
152  }
153 
154  // Post-increment operator.
155  const _IteratorTriple
156  operator++(int)
157  { return _IteratorTriple(_M_first++, _M_second++, _M_third++); }
158 
159  // Pre-decrement operator.
161  operator--()
162  {
163  --_M_first;
164  --_M_second;
165  --_M_third;
166  return *this;
167  }
168 
169  // Post-decrement operator.
170  const _IteratorTriple
171  operator--(int)
172  { return _IteratorTriple(_M_first--, _M_second--, _M_third--); }
173 
174  // Type conversion.
175  operator _Iterator3() const
176  { return _M_third; }
177 
179  operator=(const _IteratorTriple& __other)
180  {
181  _M_first = __other._M_first;
182  _M_second = __other._M_second;
183  _M_third = __other._M_third;
184  return *this;
185  }
186 
188  operator+(difference_type __delta) const
189  { return _IteratorTriple(_M_first + __delta, _M_second + __delta,
190  _M_third + __delta); }
191 
192  difference_type
193  operator-(const _IteratorTriple& __other) const
194  { return _M_first - __other._M_first; }
195  };
196 }
197 
198 #endif /* _GLIBCXX_PARALLEL_ITERATOR_H */
Includes the original header files concerned with iterators except for stream iterators....
GNU parallel code for public use.
Traits class for iterators.
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:202
_Iterator1 first
The first member.
Definition: stl_pair.h:206
_Iterator2 second
The second member.
Definition: stl_pair.h:207
A pair of iterators. The usual iterator operations are applied to both child iterators.
Definition: iterator.h:46
A triple of iterators. The usual iterator operations are applied to all three child iterators.
Definition: iterator.h:121