Undo and redo
Wandora application stores all topic map operations and user can undo these operations one by one. Reader should note that Wandora can't undo all operations but only topic map operations such as topic creation and variant name change.
Undo is performed by selecting a menu option Edit > Undo.
Successful undo generates no log messages. If undo is not possible, Wandora views a log message.
Undo buffer groups all topic map operations of an executed tool, and undo cancels every change in the group. For example, user generates topics and associations using L-system generator. Once generator finishes, user triggers undo and all topics and associations generated by the L-system generator are deleted (unless they already were in the topic map before the L-system generation).
Once a topic map operation group is undone, it can be redone by selecting a menu option Edit > Redo. Reader should note that redo option disappers after another topic map operation. It is not possible to redo a topic map operation after the topic map has changed.