Does the text widget have undo?
The text widget does not have a built-in core undo functionality, but it is possible to create such in Tcl. The method is similar to maintaining read-only sections of a text widget, whereby the programmer must catch every instance of insert and delete and store them. Depending on whether you want unlimited undo, you also want redo, or you want to capture tags as well, the exact functionality changes. Examples of working undo functionality have been posted on news:comp.lang.tcl and can be found via http://groups.google.com/advanced_group_search?as_ugroup=comp.lang.tcl.
