AutoLISP
Developer's Guide > Using the Visual
LISP Environment > Developing Programs
with Visual LISP > Using the Text
Editor > Editing a
File >
Undoing Your Last Change
You can
reverse your last edit action by choosing Edit 
Undo from the
VLISP menu bar. You can undo a virtually unlimited number of
changes, back to the point at which you last saved the file.
To reverse
the effects of the Undo command, choose Edit Redo from the
menu. Redo only works if you issue it immediately after Undo.
