Re: Implementing Undo.

["Daniel M. German" <dmg csg uwaterloo ca>]

 >> Hello hackers,
 >> 
 >> Does anyone know of software patterns for implementing Undo with
 >> different kind of changes in a document?  I want to implement
 >> Undo/Redo in Gnumeric.

What about making it generic enough that any package can use it?

How about the emacs way? The undo is infinite (well, almost :)
and the undos go back into the undo list, so you can always redo by
undoing. Recursive definition? You bet :)


--
Daniel M. German                  "When asked whether or not we are
                                   Marxists, our position is the same as
                                   that of a physicist or a biologist who
                                   is asked if he is a `Newtonian', or if
   Che Guevara ->                  he is a `Pasteurian'"
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