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diff --git a/doc/man/man3/qasciidict.3qt b/doc/man/man3/qasciidict.3qt new file mode 100644 index 00000000..4f64e644 --- /dev/null +++ b/doc/man/man3/qasciidict.3qt @@ -0,0 +1,317 @@ +'\" t +.TH QAsciiDict 3qt "2 February 2007" "Trolltech AS" \" -*- nroff -*- +.\" Copyright 1992-2007 Trolltech ASA. All rights reserved. See the +.\" license file included in the distribution for a complete license +.\" statement. +.\" +.ad l +.nh +.SH NAME +QAsciiDict \- Template class that provides a dictionary based on char* keys +.SH SYNOPSIS +\fC#include <qasciidict.h>\fR +.PP +Inherits QPtrCollection. +.PP +.SS "Public Members" +.in +1c +.ti -1c +.BI "\fBQAsciiDict\fR ( int size = 17, bool caseSensitive = TRUE, bool copyKeys = TRUE )" +.br +.ti -1c +.BI "\fBQAsciiDict\fR ( const QAsciiDict<type> & dict )" +.br +.ti -1c +.BI "\fB~QAsciiDict\fR ()" +.br +.ti -1c +.BI "QAsciiDict<type> & \fBoperator=\fR ( const QAsciiDict<type> & dict )" +.br +.ti -1c +.BI "virtual uint \fBcount\fR () const" +.br +.ti -1c +.BI "uint \fBsize\fR () const" +.br +.ti -1c +.BI "bool \fBisEmpty\fR () const" +.br +.ti -1c +.BI "void \fBinsert\fR ( const char * key, const type * item )" +.br +.ti -1c +.BI "void \fBreplace\fR ( const char * key, const type * item )" +.br +.ti -1c +.BI "bool \fBremove\fR ( const char * key )" +.br +.ti -1c +.BI "type * \fBtake\fR ( const char * key )" +.br +.ti -1c +.BI "type * \fBfind\fR ( const char * key ) const" +.br +.ti -1c +.BI "type * \fBoperator[]\fR ( const char * key ) const" +.br +.ti -1c +.BI "virtual void \fBclear\fR ()" +.br +.ti -1c +.BI "void \fBresize\fR ( uint newsize )" +.br +.ti -1c +.BI "void \fBstatistics\fR () const" +.br +.in -1c +.SS "Important Inherited Members" +.in +1c +.ti -1c +.BI "bool \fBautoDelete\fR () const" +.br +.ti -1c +.BI "void \fBsetAutoDelete\fR ( bool enable )" +.br +.in -1c +.SS "Protected Members" +.in +1c +.ti -1c +.BI "virtual QDataStream & \fBread\fR ( QDataStream & s, QPtrCollection::Item & item )" +.br +.ti -1c +.BI "virtual QDataStream & \fBwrite\fR ( QDataStream & s, QPtrCollection::Item ) const" +.br +.in -1c +.SH DESCRIPTION +The QAsciiDict class is a template class that provides a dictionary based on char* keys. +.PP +QAsciiDict is implemented as a template class. Define a template instance QAsciiDict<X> to create a dictionary that operates on pointers to X (X*). +.PP +A dictionary is a collection of key-value pairs. The key is a char* used for insertion, removal and lookup. The value is a pointer. Dictionaries provide very fast insertion and lookup. +.PP +QAsciiDict cannot handle Unicode keys; use the QDict template instead, which uses QString keys. A QDict has the same performace as a QAsciiDict. +.PP +Example: +.PP +.nf +.br + QAsciiDict<QLineEdit> fields; // char* keys, QLineEdit* values +.br + fields.insert( "forename", new QLineEdit( this ) ); +.br + fields.insert( "surname", new QLineEdit( this ) ); +.br +.br + fields["forename"]->setText( "Homer" ); +.br + fields["surname"]->setText( "Simpson" ); +.br +.br + QAsciiDictIterator<QLineEdit> it( fields ); // See QAsciiDictIterator +.br + for( ; it.current(); ++it ) +.br + cout << it.currentKey() << ": " << it.current()->text() << endl; +.br + cout << endl; +.br +.br + if ( fields["forename"] && fields["surname"] ) +.br + cout << fields["forename"]->text() << " " +.br +.br + << fields["surname"]->text() << endl; // Prints "Homer Simpson" +.br +.br + fields.remove( "forename" ); // Does not delete the line edit +.br + if ( ! fields["forename"] ) +.br + cout << "forename is not in the dictionary" << endl; +.br +.fi +In this example we use a dictionary to keep track of the line edits we're using. We insert each line edit into the dictionary with a unique name and then access the line edits via the dictionary. See QPtrDict, QIntDict and QDict. +.PP +See QDict for full details, including the choice of dictionary size, and how deletions are handled. +.PP +See also QAsciiDictIterator, QDict, QIntDict, QPtrDict, Collection Classes, Collection Classes, and Non-GUI Classes. +.SH MEMBER FUNCTION DOCUMENTATION +.SH "QAsciiDict::QAsciiDict ( int size = 17, bool caseSensitive = TRUE, bool copyKeys = TRUE )" +Constructs a dictionary optimized for less than \fIsize\fR entries. +.PP +We recommend setting \fIsize\fR to a suitably large prime number (a bit larger than the expected number of entries). This makes the hash distribution better and will improve lookup performance. +.PP +When \fIcaseSensitive\fR is TRUE (the default) QAsciiDict treats" abc" and "Abc" as different keys; when it is FALSE "abc" and" Abc" are the same. Case-insensitive comparison only considers the 26 letters in US-ASCII. +.PP +If \fIcopyKeys\fR is TRUE (the default), the dictionary copies keys using strcpy(); if it is FALSE, the dictionary just copies the pointers. +.SH "QAsciiDict::QAsciiDict ( const QAsciiDict<type> & dict )" +Constructs a copy of \fIdict\fR. +.PP +Each item in \fIdict\fR is inserted into this dictionary. Only the pointers are copied (shallow copy). +.SH "QAsciiDict::~QAsciiDict ()" +Removes all items from the dictionary and destroys it. +.PP +The items are deleted if auto-delete is enabled. +.PP +All iterators that access this dictionary will be reset. +.PP +See also setAutoDelete(). +.SH "bool QPtrCollection::autoDelete () const" +Returns the setting of the auto-delete option. The default is FALSE. +.PP +See also setAutoDelete(). +.SH "void QAsciiDict::clear ()\fC [virtual]\fR" +Removes all items from the dictionary. +.PP +The removed items are deleted if auto-deletion is enabled. +.PP +All dictionary iterators that operate on dictionary are reset. +.PP +See also remove(), take(), and setAutoDelete(). +.PP +Reimplemented from QPtrCollection. +.SH "uint QAsciiDict::count () const\fC [virtual]\fR" +Returns the number of items in the dictionary. +.PP +See also isEmpty(). +.PP +Reimplemented from QPtrCollection. +.SH "type * QAsciiDict::find ( const char * key ) const" +Returns the item associated with \fIkey\fR, or 0 if the key does not exist in the dictionary. +.PP +This function uses an internal hashing algorithm to optimize lookup. +.PP +If there are two or more items with equal keys, then the item that was most recently inserted will be found. +.PP +Equivalent to the [] operator. +.PP +See also operator[](). +.SH "void QAsciiDict::insert ( const char * key, const type * item )" +Inserts the \fIkey\fR with the \fIitem\fR into the dictionary. +.PP +Multiple items can have the same key, in which case only the last item will be accessible using operator[](). +.PP +\fIitem\fR may not be 0. +.PP +See also replace(). +.SH "bool QAsciiDict::isEmpty () const" +Returns TRUE if the dictionary is empty, i.e. count() == 0; otherwise it returns FALSE. +.PP +See also count(). +.SH "QAsciiDict<type> & QAsciiDict::operator= ( const QAsciiDict<type> & dict )" +Assigns \fIdict\fR to this dictionary and returns a reference to this dictionary. +.PP +This dictionary is first cleared and then each item in \fIdict\fR is inserted into this dictionary. Only the pointers are copied (shallow copy) unless newItem() has been reimplemented(). +.SH "type * QAsciiDict::operator[] ( const char * key ) const" +Returns the item associated with \fIkey\fR, or 0 if the key does not exist in the dictionary. +.PP +This function uses an internal hashing algorithm to optimize lookup. +.PP +If there are two or more items with equal keys, then the item that was most recently inserted will be found. +.PP +Equivalent to the find() function. +.PP +See also find(). +.SH "QDataStream & QAsciiDict::read ( QDataStream & s, QPtrCollection::Item & item )\fC [virtual protected]\fR" +Reads a dictionary item from the stream \fIs\fR and returns a reference to the stream. +.PP +The default implementation sets \fIitem\fR to 0. +.PP +See also write(). +.SH "bool QAsciiDict::remove ( const char * key )" +Removes the item associated with \fIkey\fR from the dictionary. Returns TRUE if successful, i.e. if the key existed in the dictionary; otherwise returns FALSE. +.PP +If there are two or more items with equal keys, then the most recently inserted item will be removed. +.PP +The removed item is deleted if auto-deletion is enabled. +.PP +All dictionary iterators that refer to the removed item will be set to point to the next item in the dictionary traversal order. +.PP +See also take(), clear(), and setAutoDelete(). +.SH "void QAsciiDict::replace ( const char * key, const type * item )" +Replaces an item that has a key equal to \fIkey\fR with \fIitem\fR. +.PP +If the item does not already exist, it will be inserted. +.PP +\fIitem\fR may not be 0. +.PP +Equivalent to: +.PP +.nf +.br + QAsciiDict<char> dict; +.br + ... +.br + if ( dict.find(key) ) +.br + dict.remove( key ); +.br + dict.insert( key, item ); +.br +.fi +.PP +If there are two or more items with equal keys, then the most recently inserted item will be replaced. +.PP +See also insert(). +.SH "void QAsciiDict::resize ( uint newsize )" +Changes the size of the hashtable to \fInewsize\fR. The contents of the dictionary are preserved but all iterators on the dictionary become invalid. +.SH "void QPtrCollection::setAutoDelete ( bool enable )" +Sets the collection to auto-delete its contents if \fIenable\fR is TRUE and to never delete them if \fIenable\fR is FALSE. +.PP +If auto-deleting is turned on, all the items in a collection are deleted when the collection itself is deleted. This is convenient if the collection has the only pointer to the items. +.PP +The default setting is FALSE, for safety. If you turn it on, be careful about copying the collection - you might find yourself with two collections deleting the same items. +.PP +Note that the auto-delete setting may also affect other functions in subclasses. For example, a subclass that has a remove() function will remove the item from its data structure, and if auto-delete is enabled, will also delete the item. +.PP +See also autoDelete(). +.PP +Examples: +.)l grapher/grapher.cpp, scribble/scribble.cpp, and table/bigtable/main.cpp. +.SH "uint QAsciiDict::size () const" +Returns the size of the internal hash array (as specified in the constructor). +.PP +See also count(). +.SH "void QAsciiDict::statistics () const" +Debugging-only function that prints out the dictionary distribution using qDebug(). +.SH "type * QAsciiDict::take ( const char * key )" +Takes the item associated with \fIkey\fR out of the dictionary without deleting it (even if auto-deletion is enabled). +.PP +If there are two or more items with equal keys, then the most recently inserted item will be taken. +.PP +Returns a pointer to the item taken out, or 0 if the key does not exist in the dictionary. +.PP +All dictionary iterators that refer to the taken item will be set to point to the next item in the dictionary traversal order. +.PP +See also remove(), clear(), and setAutoDelete(). +.SH "QDataStream & QAsciiDict::write ( QDataStream & s, QPtrCollection::Item ) const\fC [virtual protected]\fR" +Writes a dictionary item to the stream \fIs\fR and returns a reference to the stream. +.PP +See also read(). + +.SH "SEE ALSO" +.BR http://doc.trolltech.com/qasciidict.html +.BR http://www.trolltech.com/faq/tech.html +.SH COPYRIGHT +Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the +license file included in the distribution for a complete license +statement. +.SH AUTHOR +Generated automatically from the source code. +.SH BUGS +If you find a bug in Qt, please report it as described in +.BR http://doc.trolltech.com/bughowto.html . +Good bug reports help us to help you. Thank you. +.P +The definitive Qt documentation is provided in HTML format; it is +located at $QTDIR/doc/html and can be read using Qt Assistant or with +a web browser. This man page is provided as a convenience for those +users who prefer man pages, although this format is not officially +supported by Trolltech. +.P +If you find errors in this manual page, please report them to +.BR qt-bugs@trolltech.com . +Please include the name of the manual page (qasciidict.3qt) and the Qt +version (3.3.8). |