[Xmonad] darcs patch: Introduce NonEmptyStack.

[David Roundy]

On Fri, May 25, 2007 at 07:21:50PM -0700, David Roundy wrote:
> Hi all,
> 
> Here's a patch implementing a NonEmptyStack type that is our
> zipper without the Empty possibility.  I like this change, but
> haven't cleaned up the comments as it's not clear that others
> will like it.  I made modify accept a function that will only
> modify NonEmptyStacks, which covers all the possibilities but
> delete.
> 
> Actually, I think I'll implement a clean:q

Ooops... anyhow, this isn't particularly important (since we're in feature
freeze).  This wouldn't be a new feature, and would add more static
checking, but right now might not be the time...
-- 
David Roundy
Department of Physics
Oregon State University