Re: [Prime] any ideas for a undo function? Message #5 Posted by Tim Wessman on 4 Nov 2013, 11:49 a.m., in response to message #1 by Stefan Dröge (Germany)
The question regarding UNDO always becomes one of "to what extent and what limits?"
Do you only undo clearing of text? What about individual letter typing? What about if the user does M1:=[2] and overwrites M2, then does an UNDO? What if the user resets the app catalog? What if the user runs a user program which changes a large number of variables?
In each of these cases and thousands more, decisions have to be made regarding if, and what to do in those cases. That has to be balanced against memory, speed, expectations, and so on.
UNDO really is not a simple thing.
TW
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