1QValueListIterator(3qt)                                QValueListIterator(3qt)
2
3
4

NAME

6       QValueListIterator - Iterator for QValueList
7

SYNOPSIS

9       All the functions in this class are reentrant when Qt is built with
10       thread support.</p>
11
12       #include <qvaluelist.h>
13
14   Public Members
15       typedef T value_type
16       typedef T * pointer
17       typedef T & reference
18       QValueListIterator ()
19       QValueListIterator ( const QValueListIterator<T> & it )
20       bool operator== ( const QValueListIterator<T> & it ) const
21       bool operator!= ( const QValueListIterator<T> & it ) const
22       const T & operator* () const
23       T & operator* ()
24       QValueListIterator<T> & operator++ ()
25       QValueListIterator<T> operator++ ( int )
26       QValueListIterator<T> & operator-- ()
27       QValueListIterator<T> operator-- ( int )
28       QValueListIterator<T> & operator+= ( int j )
29       QValueListIterator<T> & operator-= ( int j )
30

DESCRIPTION

32       The QValueListIterator class provides an iterator for QValueList.
33
34       An iterator is a class for accessing the items of a container class: a
35       generalization of the index in an array. A pointer into a "const char
36       *" and an index into an "int[]" are both iterators, and the general
37       idea is to provide that functionality for any data structure.
38
39       The QValueListIterator class is an iterator for QValueList
40       instantiations. You can create the appropriate iterator type by using
41       the iterator typedef provided by QValueList.
42
43       The only way to access the items in a QValueList is to use an iterator.
44
45       Example (see QValueList for the complete code):
46
47           EmployeeList::iterator it;
48           for ( it = list.begin(); it != list.end(); ++it )
49               cout << (*it).surname().latin1() << ", " <<
50                       (*it).forename().latin1() << " earns " <<
51                       (*it).salary() << endl;
52           // Output:
53           // Doe, John earns 50000
54           // Williams, Jane earns 80000
55           // Hawthorne, Mary earns 90000
56           // Jones, Tom earns 60000
57
58       QValueList is highly optimized for performance and memory usage. This
59       means that you must be careful: QValueList does not know about all its
60       iterators and the iterators don't know to which list they belong. This
61       makes things very fast, but if you're not careful, you can get
62       spectacular bugs. Always make sure iterators are valid before
63       dereferencing them or using them as parameters to generic algorithms in
64       the STL or the QTL.
65
66       Using an invalid iterator is undefined (your application will probably
67       crash). Many Qt functions return const value lists; to iterate over
68       these you should make a copy and iterate over the copy.
69
70       For every Iterator there is a ConstIterator. When accessing a
71       QValueList in a const environment or if the reference or pointer to the
72       list is itself const, then you must use the ConstIterator. Its
73       semantics are the same as the Iterator, but it only returns const
74       references.
75
76       See also QValueList, QValueListConstIterator, Qt Template Library
77       Classes, and Non-GUI Classes.
78
79   Member Type Documentation

QValueListIterator::pointer

81       Pointer to value_type.
82

QValueListIterator::reference

84       Reference to value_type.
85

QValueListIterator::value_type

87       The type of value, T.
88

MEMBER FUNCTION DOCUMENTATION

QValueListIterator::QValueListIterator ()

91       Creates un uninitialized iterator.
92

QValueListIterator::QValueListIterator ( const QValueListIterator<T> & it )

94       This is an overloaded member function, provided for convenience. It
95       behaves essentially like the above function.
96
97       Constructs a copy of the iterator it.
98

bool QValueListIterator::operator!= ( const QValueListIterator<T> & it ) const

100
101       Compares this iterator and it and returns TRUE if they point to
102       different items; otherwise returns FALSE.
103

T & QValueListIterator::operator* ()

105       Asterisk operator. Returns a reference to the current iterator item.
106

const T & QValueListIterator::operator* () const

108       This is an overloaded member function, provided for convenience. It
109       behaves essentially like the above function.
110
111       Asterisk operator. Returns a reference to the current iterator item.
112

QValueListIterator<T> & QValueListIterator::operator++ ()

114       Prefix ++ makes the succeeding item current and returns an iterator
115       pointing to the new current item. The iterator cannot check whether it
116       reached the end of the list. Incrementing the iterator returned by
117       end() causes undefined results.
118

QValueListIterator<T> QValueListIterator::operator++ ( int )

120       This is an overloaded member function, provided for convenience. It
121       behaves essentially like the above function.
122
123       Postfix ++ makes the succeeding item current and returns an iterator
124       pointing to the new current item. The iterator cannot check whether it
125       reached the end of the list. Incrementing the iterator returned by
126       end() causes undefined results.
127

QValueListIterator<T> & QValueListIterator::operator+= ( int j )

129       Postfix -- jumps j steps forward in the list. The iterator cannot check
130       whether it reached the end of the list. Jumping past the end() causes
131       undefined results.
132

QValueListIterator<T> & QValueListIterator::operator-- ()

134       Prefix -- makes the previous item current and returns an iterator
135       pointing to the new current item. The iterator cannot check whether it
136       reached the beginning of the list. Decrementing the iterator returned
137       by begin() causes undefined results.
138

QValueListIterator<T> QValueListIterator::operator-- ( int )

140       This is an overloaded member function, provided for convenience. It
141       behaves essentially like the above function.
142
143       Postfix -- makes the previous item current and returns an iterator
144       pointing to the new current item. The iterator cannot check whether it
145       reached the beginning of the list. Decrementing the iterator returned
146       by begin() causes undefined results.
147

QValueListIterator<T> & QValueListIterator::operator-= ( int j )

149       Postfix -- jumps j steps backward in the list. The iterator cannot
150       check whether it reached the beginning of the list. Jumping past
151       begin() causes undefined results.
152

bool QValueListIterator::operator== ( const QValueListIterator<T> & it ) const

154
155       Compares this iterator and it and returns TRUE if they point to the
156       same item; otherwise returns FALSE.
157
158

SEE ALSO

160       http://doc.trolltech.com/qvaluelistiterator.html
161       http://www.trolltech.com/faq/tech.html
162
164       Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com.  See the
165       license file included in the distribution for a complete license
166       statement.
167

AUTHOR

169       Generated automatically from the source code.
170

BUGS

172       If you find a bug in Qt, please report it as described in
173       http://doc.trolltech.com/bughowto.html.  Good bug reports help us to
174       help you. Thank you.
175
176       The definitive Qt documentation is provided in HTML format; it is
177       located at $QTDIR/doc/html and can be read using Qt Assistant or with a
178       web browser. This man page is provided as a convenience for those users
179       who prefer man pages, although this format is not officially supported
180       by Trolltech.
181
182       If you find errors in this manual page, please report them to qt-
183       bugs@trolltech.com.  Please include the name of the manual page
184       (qvaluelistiterator.3qt) and the Qt version (3.3.8).
185
186
187
188Trolltech AS                    2 February 2007        QValueListIterator(3qt)
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