general undo methods?

[Richard Gaskin]

J. Landman Gay wrote:
 > On 2/18/05 6:53 PM, Richard Gaskin wrote:
 >
 >> I just spent the last two hours reading up on how undo is done in
 >> other systems, and it seems that there is no magic panaea in any of
 >> them. Good undo is simply a lot of work.
 >>
 >> The general method is to atomize your code so that every action the
 >> user can do generates undo code stored in a queue, which is then
 >> invoked when Undo is selected.
 >
 > Customers don't always understand how much work it is to implement
 > "undo", since virtually all software has it. To them, it seems like
 > it should be simple.

When we consider how far Rev has gone with the hardest part, text undo, 
I can't help but wonder if there might be some general state-recording 
mechanism that could be created in such a way as to be scalable to 
address specific needs.

But I'm also sleep-deprived, and possibly dreaming...

-- 
  Richard Gaskin
  Fourth World Media Corporation
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