[Zope] doing a "diff" of two XML export files.

[Anthony Baxter]

It seems to me that it would be a Cool Thing to be able to take
two Zope XML export files, say from different days, and feed it into 
something that would read the two, and produce a "change file" which
specifies what has changed (think "diff" for XML). 

This would be useful for

ZClass based packages, and making new versions of same.
Tracking what's done on a site on a day-by-day basis (something 
that would produce a list at the end of the day showing exactly
what changed, and where). 

Just doing a diff of the XML files is one extraordinarily yucky way
to do this, but it's not exactly easy to then reapply that as a patch.
Something that walked through the files would be more useful...

thoughts? A little bird told me that people are already considering
something for this task... any ideas?

would the XML folks have already put something like this together?

Anthony