Re: Concern about new binding.

[Gregory Heytings]

> > I misunderstood what you said indeed.  I think asking before doing 
> > anything would be okay, but I guess in that case it would be necessary 
> > to introduce an "undo-outer-outer-limit" at, say, 250 MB, above which 
> > it would not be possible to keep the undo info.
>
> Ideally, we could ask "this action will take <foo> MB; really do it?", 
> and we won't need any new variable.
>
> But like I said, I don't know how feasible this is to ask before the 
> doing the action.

In fact that option already exists (almost): undo-ask-before-discard.  It 
would make sense to set its default value to t instead of nil.  I said 
"almost" because it asks after executing the command, not before.  But at 
least it asks...