Re: Undo

[Robert Holmgren holmgren@xxxxxxxx]

** Reply to message from Harry Binswanger  on Sun, 02 Jun 2002
15:54:16 -0400


> Anyone know how Word etc. accomplish the
> undo?

Word embeds the changes within the file itself. That's why Word docs are so
huge -- one reason anyway.

U2 already has an incremental backup utility, SAVEBAK. Keeps up to 999 backups
of a file. That's a lot of UNDOs. Try it. We might add something that will
UNBAK, or go backwards through the backups, replacing the current file/screen
with the last-previous version (but keeping your place in the file), moving
backwards in reverse order to the first one (without erasing those backups; I
dunno, does Word or any other program have a way of reversing an UNDO? can you
UNDO an UNDO (=RESTOREDO)? SAVEBAK gives you that, in effect -- a feature other
WPs don't have maybe...) If you have a KBD key dedicated to SAving (doesn't
everybody?), you might change it to perform a SAVEBAK -- then SAVEBAK often,
especially before CHanges.

Writing a real UNDO would be a pain in the you-know-what. What, precisely,
would you UNDO? Every keystroke? Only "major" alterations? What's major,
what's minor? U2 has utils that preserve deletions; you can always regurgitate
a tossed paragraph if you change your mind. We have a util (Stack) that
remembers all your commands, even if you turn off your computer. So if you use
it resourcefully, U2 already contains the components of a massive amount of UNDO.

-----------------------------
Robert Holmgren
holmgren@xxxxxxxx
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