summaryrefslogtreecommitdiffstats
path: root/qtools/qlist.doc
blob: 6b4278cc7b7f942b58bd048b4e0643bae72aff70 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
/****************************************************************************
** 
**
** QList and QListIterator class documentation
**
** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
**
** This file is part of the Qt GUI Toolkit.
**
** This file may be distributed under the terms of the Q Public License
** as defined by Trolltech AS of Norway and appearing in the file
** LICENSE.QPL included in the packaging of this file.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
**
** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition
** licenses may use this file in accordance with the Qt Commercial License
** Agreement provided with the Software.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for
**   information about Qt Commercial License Agreements.
** See http://www.trolltech.com/qpl/ for QPL licensing information.
** See http://www.trolltech.com/gpl/ for GPL licensing information.
**
** Contact info@trolltech.com if any conditions of this licensing are
** not clear to you.
**
**********************************************************************/


/*****************************************************************************
  QList documentation
 *****************************************************************************/

/*!
  \class QList qlist.h
  \brief The QList class is a template class that provides doubly linked lists.

  \ingroup collection
  \ingroup tools

  In Qt 2.0 QList is only implemented as a template class. Define a
  template instance QList\<X\> to create a list that operates on pointers
  to X, or X*.

  Example:
  \code
    #include <qlist.h>
    #include <qstring.h>
    #include <stdio.h>

    class Employee
    {
    public:
        Employee( const QString& name, int salary ) { n=name; s=salary; }
        QString     name()   const		 { return n; }
        int	    salary() const		 { return s; }
    private:
        QString     n;
        int         s;
    };

    void main()
    {
	QList<Employee> list;		// list of pointers to Employee
	list.setAutoDelete( TRUE );	// delete items when they are removed

	list.append( new Employee("Bill", 50000) );
	list.append( new Employee("Steve",80000) );
	list.append( new Employee("Ron",  60000) );

	Employee *emp;
	for ( emp=list.first(); emp != 0; emp=list.next() )
	    printf( "%s earns %d\n", emp->name().latin1(), emp->salary() );
    }
  \endcode

  Program output:
  \code
	Bill earns 50000
	Steve earns 80000
	Ron earns 60000
  \endcode

  The list class is indexable and has a \link at() current index\endlink
  and a \link current() current item\endlink.  The first item corresponds
  to index 0.  The current index is -1 if the current item is null.

  QList has several member functions for traversing the list, but using
  a QListIterator can be more practical. Multiple list iterators may
  traverse the same list, independent of each other and independent of
  the current list item.

  In the example above, we make the call setAutoDelete(TRUE).
  Enabling auto-deletion tells the list to delete items that are removed
  from the list.  The default is to not delete items when they are
  removed, but that would cause a memory leak in our example since we have
  no other references to the list items.

  List items are stored as \c void* in an internal QLNode, which also
  holds pointers to the next and previous list items.  The functions
  currentNode(), removeNode() and takeNode() operate directly on the
  QLNode, but they should be used with care.

  When inserting an item into a list, only the pointer is copied, not the
  item itself. This is called a shallow copy. It is possible to make the
  list copy all of the item's data (known as a deep copy) when an item is
  inserted.  insert(), inSort() and append() call the virtual function
  QCollection::newItem() for the item to be inserted.
  Inherit a list and reimplement it if you want deep copies.

  When removing an item from a list, the virtual function
  QCollection::deleteItem() is called.  QList's default implementation
  is to delete the item if auto-deletion is enabled.

  The virtual function QGList::compareItems() can be reimplemented to
  compare two list items. This function is called from all list functions
  that need to compare list items, for instance remove(const type*).
  If you only want to deal with pointers, there are functions that
  compare pointers instead, for instance removeRef(const type*).
  These functions are somewhat faster than those that call compareItems().

  The QStrList class in qstrlist.h is a list of \c char*.  QStrList is
  a good example of a list that reimplements newItem(), deleteItem() and
  compareItems()

  \sa QListIterator, \link collection.html Collection Classes\endlink
*/


/*!
  \fn QList::QList()
  Constructs an empty list.
*/

/*!
  \fn QList::QList( const QList<type> &list )
  Constructs a copy of \e list.

  Each item in \e list is \link append() appended\endlink to this list.
  Only the pointers are copied (shallow copy).
*/

/*!
  \fn QList::~QList()
  Removes all items from the list and destroys the list.

  All list iterators that access this list will be reset.

  \sa setAutoDelete()
*/

/*!
  \fn QList<type> &QList::operator=(const QList<type> &list)
  Assigns \e list to this list and returns a reference to this list.

  This list is first cleared, then each item in \e list is
  \link append() appended\endlink to this list.  Only the pointers are copied
  (shallow copy), unless newItem() has been reimplemented().
*/

/*!
  \fn bool QList::operator==(const QList<type> &list ) const

  Compares this list with \a list. Retruns TRUE if the lists
  contain the same data, else FALSE.
*/

/*!
  \fn uint QList::count() const
  Returns the number of items in the list.
  \sa isEmpty()
*/

/*!
  \fn void QList::sort()

  Sorts the list by the result of the virtual compareItems() function.

  The Heap-Sort algorithm is used for sorting.  It sorts n items with
  O(n*log n) compares.  This is the asymptotic optimal solution of the
  sorting problem.

  If the items in your list support operator< and operator== then you
  might be better off with QSortedList since it implements the
  compareItems() function for you using these two operators.

  \sa inSort()
*/

/*!
  \fn bool QList::isEmpty() const
  Returns TRUE if the list is empty, i.e. count() == 0. Returns FALSE
   otherwise.
  \sa count()
*/

/*!
  \fn bool QList::insert( uint index, const type *item )
  Inserts the \e item at the position \e index in the list.

  Returns TRUE if successful, or FALSE if \e index is out of range.
  The valid range is <code>0 .. count()</code> inclusive.
  The item is appended if \e index == count().

  The inserted item becomes the current list item.

  The \e item must not be a null pointer.

  \sa append(), current()
*/

/*!
  \fn void QList::inSort( const type *item )
  Inserts the \e item at its sorted position in the list.

  The sort order depends on the virtual QGList::compareItems() function.
  All items must be inserted with inSort() to maintain the sorting order.

  The inserted item becomes the current list item.

  The \e item must not be a null pointer.

  Please note that inSort is slow. If you want to insert lots of items
  in a list and sort after inserting then you should use sort().
  inSort() takes up to O(n) compares. That means inserting n items in
  your list will need O(n^2) compares while sort() only needs O(n*logn)
  for the same task. So you inSort() only if you already have a pre-sorted
  list and want to insert only few additional items.

  \sa insert(), QGList::compareItems(), current(), sort()
*/

/*!
  \fn void QList::append( const type *item )
  Inserts the \e item at the end of the list.

  The inserted item becomes the current list item.
  This is equivalent to \c insert(count(),item).


  The \e item must not be a null pointer.

  \sa insert(), current(), prepend()
*/

/*!
  \fn void QList::prepend( const type *item )

  Inserts the \e item at the start of the list.

  The inserted item becomes the current list item.
  This is equivalent to \c insert(0,item).

  The \e item must not be a null pointer.

  \sa append(), insert(), current()
*/

/*!
  \fn bool QList::remove( uint index )
  Removes the item at position \e index in the list.

  Returns TRUE if successful, or FALSE if \e index is out of range.
  The valid range is <code>0 .. (count() - 1)</code> inclusive.

  The removed item is deleted if \link QCollection::setAutoDelete()
  auto-deletion\endlink is enabled.

  The item after the removed item becomes the new current list item if
  the removed item is not the last item in the list.  If the last item
  is removed, the new last item becomes the current item in Qt 2.x.
  In 3.0, the current item will be set to null.  The current item is
  set to null if the list becomes empty.

  All list iterators that refer to the removed item will be set to point
  to the new current item.

  \sa take(), clear(), setAutoDelete(), current() removeRef()
*/

/*!
  \fn bool QList::remove()
  Removes the current list item.

  Returns TRUE if successful, or FALSE if the current item is null.

  The removed item is deleted if \link QCollection::setAutoDelete()
  auto-deletion\endlink is enabled.

  The item after the removed item becomes the new current list item if
  the removed item is not the last item in the list.  If the last item
  is removed, the new last item becomes the current item in Qt 2.x.
  In 3.0, the current item will be set to null.  The current item is
  set to null if the list becomes empty.

  All list iterators that refer to the removed item will be set to point
  to the new current item.

  \sa take(), clear(), setAutoDelete(), current() removeRef()
*/

/*!
  \fn bool QList::remove( const type *item )
  Removes the first occurrence of \e item from the list.

  Returns TRUE if successful, or FALSE if the item could not be found in the
  list.

  The removed item is deleted if \link QCollection::setAutoDelete()
  auto-deletion\endlink is enabled.

  The compareItems() function is called when searching for the item
  in the list. If compareItems() is not reimplemented, it is more
  efficient to call removeRef().

  The item after the removed item becomes the new current list item if
  the removed item is not the last item in the list.  If the last item
  is removed, the new last item becomes the current item in Qt 2.x.
  In 3.0, the current item will be set to null.  The current item is
  set to null if the list becomes empty.

  All list iterators that refer to the removed item will be set to point
  to the new current item.

  \sa removeRef(), take(), clear(), setAutoDelete(), compareItems(), current()
*/

/*!
  \fn bool QList::removeRef( const type *item )
  Removes the first occurrence of \e item from the list.

  Returns TRUE if successful, or FALSE if the item cannot be found in the
  list.

  The removed item is deleted if \link QCollection::setAutoDelete()
  auto-deletion\endlink is enabled.

  The list is scanned until the pointer \e item is found.  It is removed
  if it is found.

  Equivalent to:
  \code
    if ( list.findRef(item) != -1 )
	list.remove();
  \endcode

  The item after the removed item becomes the new current list item if
  the removed item is not the last item in the list.  If the last item
  is removed, the new last item becomes the current item in Qt 2.x.
  In 3.0, the current item will be set to null.  The current item is
  set to null if the list becomes empty.

  All list iterators that refer to the removed item will be set to point
  to the new current item.

  \sa remove(), clear(), setAutoDelete(), current()
*/

/*!
  \fn void QList::removeNode( QLNode *node )
  Removes the \e node from the list.

  This node must exist in the list, otherwise the program may crash.

  The removed item is deleted if \link QCollection::setAutoDelete()
  auto-deletion\endlink is enabled.

  The first item in the list will become the new current list item.
  The current item is set to null if the list becomes empty.

  All list iterators that refer to the removed item will be set to point to
  the item succeeding this item, or the preceding item if the removed item
  was the last item.

  \warning Do not call this function unless you are an expert.

  \sa takeNode(), currentNode() remove() removeRef()
*/

/*!
  \fn bool QList::removeFirst()
  Removes the first item from the list.
  Returns TRUE if successful, or FALSE if the list is empty.

  The removed item is deleted if \link QCollection::setAutoDelete()
  auto-deletion\endlink is enabled.

  The first item in the list becomes the new current list item.
  The current item is set to null if the list becomes empty.

  All list iterators that refer to the removed item will be set to point
  to the new current item.

  \sa removeLast(), setAutoDelete(), current() remove()
*/

/*!
  \fn bool QList::removeLast()
  Removes the last item from the list.
  Returns TRUE if successful, or FALSE if the list is empty.

  The removed item is deleted if \link QCollection::setAutoDelete()
  auto-deletion\endlink is enabled.

  The last item in the list becomes the new current list item.
  The current item is set to null if the list becomes empty.

  All list iterators that refer to the removed item will be set to point
  to the new current item.

  \sa removeFirst(), setAutoDelete(), current()
*/

/*!
  \fn type *QList::take( uint index )
  Takes the item at position \e index out of the list without
  deleting it (even if \link QCollection::setAutoDelete()
  auto-deletion\endlink is enabled).

  Returns a pointer to the item taken out of the list, or null if
  the index is out of range.
  The valid range is <code>0 .. (count() - 1)</code> inclusive.

  The item after the taken item becomes the new current list item if
  the taken item is not the last item in the list.  If the last item
  is taken, the new last item becomes the current item in Qt 2.x.  In
  3.0, the current item will be set to null.  The current item is set
  to null if the list becomes empty.

  All list iterators that refer to the taken item will be set to point to
  the new current item.

  \sa remove(), clear(), current()
*/

/*!
  \fn type *QList::take()
  Takes the current item out of the list without deleting it (even if
  \link QCollection::setAutoDelete() auto-deletion\endlink is enabled).
  Returns a pointer to the item taken out of the list, or null if
  the current item is null.

  The item after the taken item becomes the new current list item if
  the taken item is not the last item in the list.  If the last item
  is taken, the new last item becomes the current item in Qt 2.x.  In
  3.0, the current item will be set to null.  The current item is set
  to null if the list becomes empty.

  All list iterators that refer to the taken item will be set to point to
  the new current item.

  \sa remove(), clear(), current()
*/

/*!
  \fn type *QList::takeNode( QLNode *node )
  Takes the \e node out of the list without deleting its item (even if
  \link QCollection::setAutoDelete() auto-deletion\endlink is enabled).
  Returns a pointer to the item taken out of the list.

  This node must exist in the list, otherwise the program may crash.

  The first item in the list becomes the new current list item.

  All list iterators that refer to the taken item will be set to point to
  the item succeeding this item, or the preceding item if the taken item
  was the last item.

  \warning Do not call this function unless you are an expert.

  \sa removeNode(), currentNode()
*/

/*!
  \fn void QList::clear()
  Removes all items from the list.

  The removed items are deleted if \link QCollection::setAutoDelete()
  auto-deletion\endlink is enabled.

  All list iterators that access this list will be reset.

  \sa remove(), take(), setAutoDelete()
*/

/*!
  \fn int QList::find( const type *item )
  Finds the first occurrence of \e item in the list.

  If the item is found, the list sets the current item to point to
  the found item and returns the index of this item.
  If the item is not found, the list sets the current item to null,
  the current index to -1 and returns -1.

  The compareItems() function is called when searching for the item
  in the list. If compareItems() is not reimplemented, it is more
  efficient to call findRef().

  \sa findNext(), findRef(), compareItems(), current()
*/

/*!
  \fn int QList::findNext( const type *item )
  Finds the next occurrence of \e item in the list, starting from
  the current list item.

  If the item is found, the list sets the current item to point to
  the found item and returns the index of this item.
  If the item is not found, the list sets the current item to null,
  the current index to -1 and returns -1.

  The compareItems() function is called when searching for the item
  in the list. If compareItems() is not reimplemented, it is more
  efficient to call findNextRef().

  \sa find(), findNextRef(), compareItems(), current()
*/

/*!
  \fn int QList::findRef( const type *item )
  Finds the first occurrence of \e item in the list.

  If the item is found, the list sets the current item to point to
  the found item and returns the index of this item.
  If the item is not found, the list sets the current item to null,
  the current index to -1 and returns -1.

  Calling this function is must faster than find(), because find()
  compares \e item with each list item using compareItems().
  This function only compares the pointers.

  \sa findNextRef(), find(), current()
*/

/*!
  \fn int QList::findNextRef( const type *item )
  Finds the next occurrence of \e item in the list, starting from the
  current list item.

  If the item is found, the list sets the current item to point to
  the found item and returns the index of this item.
  If the item is not found, the list sets the current item to null,
  the current index to -1 and returns -1.

  Calling this function is must faster than findNext(), because findNext()
  compares \e item with each list item using compareItems().
  This function only compares the pointers.

  \sa findRef(), findNext(), current()
*/

/*!
  \fn uint QList::contains( const type *item ) const
  Counts and returns the number of occurrences of \e item in the list.

  The compareItems() function is called when looking for the \e item
  in the list. If compareItems() is not reimplemented, it is more
  efficient to call containsRef().

  Does not affect the current list item.

  \sa containsRef(), compareItems()
*/

/*!
  \fn uint QList::containsRef( const type *item ) const
  Counts and returns the number of occurrences of \e item in the list.

  Calling this function is must faster than contains(), because contains()
  compares \e item with each list item using compareItems().
  This function only compares the pointers.

  Does not affect the current list item.

  \sa contains()
*/

/*!
  \fn type *QList::at( uint index )
  Returns a pointer to the item at position \e index in the list, or
  null if the index is out of range.

  Sets the current list item to this item if \e index is valid.
  The valid range is <code>0 .. (count() - 1)</code> inclusive.

  This function is very efficient.  It starts scanning from the first
  item, last item or current item, whichever is closest to \e index.

  \sa current()
*/

/*!
  \fn int QList::at() const
  Returns the index of the current list item.  The returned value is -1
  if the current item is null.
  \sa current()
*/

/*!
  \fn type *QList::current() const
  Returns a pointer to the current list item.  The current item may be
  null (implies that the current index is -1).
  \sa at()
*/

/*!
  \fn QLNode *QList::currentNode() const
  Returns a pointer to the current list node.

  The node can be kept and removed later using removeNode().
  The advantage is that the item can be removed directly without
  searching the list.

  \warning Do not call this function unless you are an expert.

  \sa removeNode(), takeNode(), current()
*/

/*!
  \fn type *QList::getFirst() const
  Returns a pointer to the first item in the list, or null if the
  list is empty.

  Does not affect the current list item.

  \sa first(), getLast()
*/

/*!
  \fn type *QList::getLast() const
  Returns a pointer to the last item in the list, or null if the
  list is empty.

  Does not affect the current list item.

  \sa last(), getFirst()
*/

/*!
  \fn type *QList::first()
  Returns a pointer to the first item in the list and makes this the
  current list item, or null if the list is empty.
  \sa getFirst(), last(), next(), prev(), current()
*/

/*!
  \fn type *QList::last()
  Returns a pointer to the last item in the list and makes this the
  current list item, or null if the list is empty.
  \sa getLast(), first(), next(), prev(), current()
*/

/*!
  \fn type *QList::next()
  Returns a pointer to the item succeeding the current item.
  Returns null if the current item is null or equal to the last item.

  Makes the succeeding item current. If the current item before this
  function call was the last item, the current item will be set to null.
  If the current item was null, this function does nothing.

  \sa first(), last(), prev(), current()
*/

/*!
  \fn type *QList::prev()
  Returns a pointer to the item preceding the current item.
  Returns null if the current item is null or equal to the first item.

  Makes the preceding item current. If the current item before this
  function call was the first item, the current item will be set to null.
  If the current item was null, this function does nothing.

  \sa first(), last(), next(), current()
*/

/*!
  \fn void QList::toVector( QGVector *vec ) const
  Stores all list items in the vector \e vec.

  The vector must be have the same item type, otherwise the result
  will be undefined.
*/


/*****************************************************************************
  QListIterator documentation
 *****************************************************************************/

/*!
  \class QListIterator qlist.h
  \brief The QListIterator class provides an iterator for QList collections.

  \ingroup collection
  \ingroup tools

  Define a template instance QListIterator\<X\> to create a list iterator
  that operates on QList\<X\> (list of X*).

  Example:
  \code
    #include <qlist.h>
    #include <qstring.h>
    #include <stdio.h>

    class Employee
    {
    public:
        Employee( const char *name, int salary ) { n=name; s=salary; }
        const char *name()   const		 { return n; }
        int	    salary() const		 { return s; }
    private:
        QString     n;
        int         s;
    };

    void main()
    {
	QList<Employee> list;		  // list of pointers to Employee
	list.setAutoDelete( TRUE );	  // delete items when they are removed

	list.append( new Employee("Bill", 50000) );
	list.append( new Employee("Steve",80000) );
	list.append( new Employee("Ron",  60000) );

	QListIterator<Employee> it(list); // iterator for employee list
	for ( ; it.current(); ++it ) {
	    Employee *emp = it.current();
	    printf( "%s earns %d\n", emp->name().latin1(), emp->salary() );
        }
    }
  \endcode

  Program output:
  \code
	Bill earns 50000
	Steve earns 80000
	Ron earns 60000
  \endcode

  Although QList has member functions to traverse the doubly linked list
  structure, using a list iterator is a much more robust way of traversing
  the list, because multiple list iterators can operate on the same list,
  independent of each other and independent of the QList's current item.
  An iterator has its own current list item and can get the next and
  previous list items.  It can only traverse the list, never modify it.

  A QList knows about all list iterators that are operating on the list.
  When an item is removed from the list, the list update all iterators
  that are pointing the removed item to point to the new current list item.

  Example:
  \code
    #include <qlist.h>
    #include <qstring.h>
    #include <stdio.h>

    class Employee
    {
	...	// same as above
    };

    void main()
    {
	QList<Employee> list;		  // list of pointers to Employee
	list.setAutoDelete( TRUE );	  // delete items when they are removed

	list.append( new Employee("Bill", 50000) );
	list.append( new Employee("Steve",80000) );
	list.append( new Employee("Ron",  60000) );

	QListIterator<Employee> it(list);

	list.at( 1 );			  // current list item: "Steve"
        it.toLast();			  // it: "Ron"
	--it;				  // it: "Steve"

	  // Now, both the list and the iterator are referring the same item

	list.remove();
	printf( "%s\n", it.current()->name().latin1() );
    }
  \endcode

  Program output:
  \code
	Ron
  \endcode

  \sa QList, \link collection.html collection classes\endlink
*/

/*!
  \fn QListIterator::QListIterator( const QList<type> &list )
  Constructs an iterator for \e list.  The current iterator item is
  set to point on the first item in the \e list.
*/

/*!
  \fn QListIterator::~QListIterator()
  Destroys the iterator.
*/

/*!
  \fn uint QListIterator::count() const
  Returns the number of items in the list this iterator operates on.
  \sa isEmpty()
*/

/*!
  \fn bool QListIterator::isEmpty() const
  Returns TRUE if the list is empty, i.e. count() == 0, otherwise FALSE.
  \sa count()
*/

/*!
  \fn bool QListIterator::atFirst() const
  Returns TRUE if the current iterator item is the first list item, otherwise
  FALSE.
  \sa toFirst(), atLast()
*/

/*!
  \fn bool QListIterator::atLast() const
  Returns TRUE if the current iterator item is the last list item, otherwise
  FALSE.
  \sa toLast(), atFirst()
*/

/*!
  \fn type *QListIterator::toFirst()
  Sets the current iterator item to point to the first list item and returns
  a pointer to the item.  Sets the current item to null and returns null
  if the list is empty.
  \sa toLast(), atFirst()
*/

/*!
  \fn type *QListIterator::toLast()
  Sets the current iterator item to point to the last list item and returns
  a pointer to the item.  Sets the current item to null and returns null
  if the list is empty.
  \sa toFirst(), atLast()
*/

/*!
  \fn QListIterator::operator type *() const
  Cast operator. Returns a pointer to the current iterator item.
  Same as current().
*/

/*!
  \fn type *QListIterator::operator*()
  Asterix operator. Returns a pointer to the current iterator item.
  Same as current().
*/

/*!
  \fn type *QListIterator::current() const
  Returns a pointer to the current iterator item.
*/

/*!
  \fn type *QListIterator::operator()()
  Makes the succeeding item current and returns the original current item.

  If the current iterator item was the last item in the list or if it was
  null, null is returned.
*/

/*!
  \fn char *QStrListIterator::operator()()
  Makes the succeeding item current and returns the original current item.

  If the current iterator item was the last item in the list or if it was
  null, null is returned.
*/

/*!
  \fn type *QListIterator::operator++()
  Prefix ++ makes the succeeding item current and returns the new current
  item.

  If the current iterator item was the last item in the list or if it was
  null, null is returned.
*/

/*!
  \fn type *QListIterator::operator+=( uint jump )
  Sets the current item to the item \e jump positions after the current item,
  and returns a pointer to that item.

  If that item is beyond the last item or if the dictionary is  empty,
  it sets the current item to null and  returns null
*/

/*!
  \fn type *QListIterator::operator--()
  Prefix -- makes the preceding item current and returns the new current
  item.

  If the current iterator item was the first item in the list or if it was
  null, null is returned.
*/

/*!
  \fn type *QListIterator::operator-=( uint jump )
  Returns the item \e jump positions before the current item, or null if
  it is beyond the first item.  Makes this the current item.
*/

/*!
  \fn QListIterator<type>& QListIterator::operator=( const QListIterator<type> &it )
  Assignment.  Makes a copy of the iterator \a it and returns a reference
  to this iterator.
*/


/*****************************************************************************
  QStrList documentation
 *****************************************************************************/

//typedef QList<char> QStrList

/*!
  \class QStrList qstrlist.h
  \brief The QStrList class provides a doubly linked list of \c char*.

  \ingroup collection
  \ingroup tools

  This class is a QList\<char\> instance (a list of char*).

  QStrList can make deep or shallow copies of the strings that are inserted.

  A deep copy means to allocate space for the string and then copy the string
  data into it.  A shallow copy is just a copy of the pointer value and not
  the string data.

  The disadvantage with shallow copies is that since a pointer can only
  be deleted once, the program must put all strings in a central place and
  know when it is safe to delete them (i.e. when the strings are no longer
  referenced by other parts of the program).  This can make the program
  more complex.  The advantage of shallow copies is that shallow copies
  consume far less memory than deep copies.  It is also much faster
  to copy a pointer (typically 4 or 8 bytes) than to copy string data.

  A QStrList that operates on deep copies will by default turn on
  auto-deletion (see setAutoDelete()). Thus, by default, QStrList will
  deallocate any string copies it allocates.

  The virtual compareItems() function is reimplemented and does a case
  sensitive string comparison. The inSort() function will insert
  strings in a sorted order.

  The QStrListIterator class is an iterator for QStrList.
*/

/*!
  \fn QStrList::QStrList( bool deepCopies )
  Constructs an empty list of strings.  Will make deep copies of all inserted
  strings if \e deepCopies is TRUE, or uses shallow copies if \e deepCopies
  is FALSE.
*/

/*!
  \fn QStrList::QStrList( const QStrList &list )
  Constructs a copy of \e list.

  If \e list has deep copies, this list will also get deep copies.
  Only the pointers are copied (shallow copy) if the other list does not
  use deep copies.
*/

/*!
  \fn QStrList::~QStrList()
  Destroys the list.  All strings are removed.
*/

/*!
  \fn QStrList& QStrList::operator=( const QStrList& list )
  Assigns \e list to this list and returns a reference to this list.

  If \e list has deep copies, this list will also get deep copies.
  Only the pointers are copied (shallow copy) if the other list does not
  use deep copies.
*/


/*****************************************************************************
  QStrIList documentation
 *****************************************************************************/

/*!
  \class QStrIList qstrlist.h
  \brief The QStrIList class provides a doubly linked list of \c char* with
case insensitive compare.

  \ingroup collection
  \ingroup tools

  This class is a QList\<char\> instance (a list of char*).

  QStrIList is similar to QStrList except that it is case insensitive.
  The virtual compareItems() function is reimplemented and does a
  case insensitive string comparison.
  The inSort() function will insert strings in a sorted order.

  The QStrListIterator class is an iterator for QStrList.
*/

/*!
  \fn QStrIList::QStrIList( bool deepCopies )
  Constructs a list of strings.  Will make deep copies of all inserted
  strings if \e deepCopies is TRUE, or uses shallow copies if \e deepCopies
  is FALSE.
*/

/*!
  \fn QStrIList::~QStrIList()
  Destroys the list.  All strings are removed.
*/


/*****************************************************************************
  QStrListIterator documentation
 *****************************************************************************/

/*!
  \class QStrListIterator qstrlist.h
  \brief The QStrListIterator class is an iterator for the QStrList and QStrIList classes.

  \ingroup tools

  This class is a QListIterator\<char\> instance.
  It can traverse the strings in the QStrList and QStrIList classes.
*/