^TI^'
^TITW^history 
^TITW^redo 
^TIS^eventSpec 
^TI^' Command
^P^
Re-executes the command indicated by the optional argument 
^S^eventSpec
 and returns its result. 
^S^eventSpec
 defaults to -1, if not given. This command results in history revision; 
see the Tcl man page for details.
