Tulip  5.2.0
Large graphs analysis and drawing
StlIterator.h
1 /*
2  *
3  * This file is part of Tulip (http://tulip.labri.fr)
4  *
5  * Authors: David Auber and the Tulip development Team
6  * from LaBRI, University of Bordeaux
7  *
8  * Tulip is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU Lesser General Public License
10  * as published by the Free Software Foundation, either version 3
11  * of the License, or (at your option) any later version.
12  *
13  * Tulip is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
16  * See the GNU General Public License for more details.
17  *
18  */
19 
20 #ifndef TULIP_STLITERATOR_H
21 #define TULIP_STLITERATOR_H
22 
23 #include <map>
24 #include <type_traits>
25 
26 #include <tulip/Iterator.h>
27 #include <tulip/memorypool.h>
28 
29 namespace tlp {
30 
31 /**
32 * @class StlIterator
33 * @ingroup Iterators
34 *
35 * @brief StlIterator wraps a stl iterator.
36 *
37 * Creates a Tulip Iterator from two stl iterators.
38 *
39 * @param startIt a stl iterator from which to begin the iteration
40 * @param endIt a stl iterator on which to end the iteration
41 *
42 **/
43 template <typename T, typename ITERATOR>
44 struct StlIterator : public Iterator<T> {
45  StlIterator(const ITERATOR &startIt, const ITERATOR &endIt) : it(startIt), itEnd(endIt) {}
46  T next() {
47  T tmp = *it;
48  ++it;
49  return tmp;
50  }
51  bool hasNext() {
52  return (itEnd != it);
53  }
54 
55 private:
56  ITERATOR it, itEnd;
57 };
58 //=================================================
59 template <typename T, typename ITERATOR>
60 struct MPStlIterator : public StlIterator<T, ITERATOR>,
61  public MemoryPool<MPStlIterator<T, ITERATOR>> {
62  MPStlIterator(const ITERATOR &startIt, const ITERATOR &endIt)
63  : StlIterator<T, ITERATOR>(startIt, endIt) {}
64 };
65 //=================================================
66 
67 // Helper to determine whether there's a const_iterator for T.
68 template <typename T>
69 struct has_const_iterator {
70 private:
71  template <typename C>
72  static char test(typename C::const_iterator *);
73  template <typename C>
74  static int test(...);
75 
76 public:
77  enum { value = sizeof(test<T>(0)) == sizeof(char) };
78 };
79 
80 /**
81 * @brief Convenient function for creating a StlIterator from a stl container.
82 * @ingroup Iterators
83 *
84 * @since Tulip 5.2
85 *
86 * Creates a StlIterator from a STL container (std::list, std::vector, std::set, std::map, ...).
87 *
88 * @param stlContainer any STL container
89 * @return a StlIterator
90 **/
91 template <typename Container>
92 typename std::enable_if<
93  has_const_iterator<Container>::value,
95  *>::type inline stlIterator(const Container &stlContainer) {
96  return new MPStlIterator<typename Container::value_type, typename Container::const_iterator>(
97  stlContainer.begin(), stlContainer.end());
98 }
99 
100 //=================================================
101 template <typename KEY, typename VALUE>
102 struct StlMapIterator : public Iterator<std::pair<KEY, VALUE>> {
103  StlMapIterator(typename std::map<KEY, VALUE>::const_iterator startIt,
104  typename std::map<KEY, VALUE>::const_iterator endIt)
105  : it(startIt), itEnd(endIt) {}
106 
107  std::pair<KEY, VALUE> next() {
108  std::pair<KEY, VALUE> tmp = *it;
109  ++it;
110  return tmp;
111  }
112 
113  bool hasNext() {
114  return (itEnd != it);
115  }
116 
117 private:
118  typename std::map<KEY, VALUE>::const_iterator it, itEnd;
119 };
120 //=================================================
121 template <typename KEY, typename VALUE>
122 struct StlMapKeyIterator : public tlp::Iterator<KEY> {
123  StlMapKeyIterator(typename std::map<KEY, VALUE>::const_iterator startIt,
124  typename std::map<KEY, VALUE>::const_iterator endIt)
125  : it(startIt), itEnd(endIt) {}
126 
127  KEY next() {
128  const KEY tmp = it->first;
129  ++it;
130  return tmp;
131  }
132 
133  bool hasNext() {
134  return it != itEnd;
135  }
136 
137 private:
138  typename std::map<KEY, VALUE>::const_iterator it, itEnd;
139 };
140 }
141 
142 #endif
Interface for Tulip iterators. Allows basic iteration operations only.
Definition: Graph.h:41
StlIterator wraps a stl iterator.
Definition: StlIterator.h:44
T next()
Moves the Iterator on the next element.
Definition: StlIterator.h:46
std::enable_if< has_const_iterator< Container >::value, StlIterator< typename Container::value_type, typename Container::const_iterator > * >::type stlIterator(const Container &stlContainer)
Convenient function for creating a StlIterator from a stl container.
Definition: StlIterator.h:95
bool hasNext()
Tells if the sequence is at its end.
Definition: StlIterator.h:51