From xemacs-m  Sun Feb  2 02:12:55 1997
Received: from crystal.WonderWorks.COM (crystal.WonderWorks.com [192.203.206.1])
	by xemacs.org (8.8.5/8.8.5) with ESMTP id CAA12661
	for <xemacs-beta@xemacs.org>; Sun, 2 Feb 1997 02:12:54 -0600 (CST)
Received: by crystal.WonderWorks.COM 
	id QQcbcy21584; Sun, 2 Feb 1997 03:12:49 -0500 (EST)
Date: Sun, 2 Feb 1997 03:12:49 -0500 (EST)
Message-Id: <QQcbcy21584.199702020812@crystal.WonderWorks.COM>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
From: Kyle Jones <kyle_jones@wonderworks.com>
To: xemacs-beta@xemacs.org
Subject: Re: Undo!
In-Reply-To: <199702020758.CAA04094@localhost.interport.net>
References: <199702010502.AAA03861@localhost.interport.net>
	<kign2tozwpd.fsf@jagor.srce.hr>
	<QQcbcr19912.199702020628@crystal.WonderWorks.COM>
	<199702020758.CAA04094@localhost.interport.net>

Peter Pezaris writes:
 > 
 >     Kyle> Can someone explain what a redo is supposed to do?
 > 
 >     Kyle> I like Emacs' undo system, probably because my mind
 >     Kyle> doesn't have trouble chasing and remembering long chains
 >     Kyle> of pointers.  The direction reversals and all that seem
 >     Kyle> imminently logical to me.
 > 
 > You're editing a file.  You go to the beginning of the file and do a
 > batch of non-trivial editing.  Later, you go to a different part of
 > the file and do another batch of non-trivial editing.  Then it hits
 > you; the first batch of editing has a mistake in it that you have to
 > change.  You hit undo 47 times to get back to that point, and change
 > the thing that needs to get changed.  Wouldn't it be nice to hit
 > "redo" 47 times to get back to where you really want to be?

It sounds really complicated.  How do you keep track of the
partitioning that this system obviously has to use?  How do you
know what it is going to undo/redo?  I'm sure the code knows, but
how do YOU (the user) know?  If your intervening edits have
shifted/deleted text that is going be re-edited, it sounds like
it will be a terrible mess to figure out what will happen.

