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Re: disjointness of '() and #f

Another factor arguing for disjointness has been raised but unstated for
some time.  Disjointness [(eq? '() #f) -> #f] is much easier to explain
to students as it accords with their intuitive notions.  There are areas
where Scheme differs from naive intuition for deep reasons (e.g.
exactness).  It would be nice to be able to concentrate on areas where
there really are deep issues rather than areas of happenstance.

I see no problem with making disjointness of predicates BOOLEAN? and
NULL? in the IEEE Scheme Standard and allowing (e.g. Jinx) to redefine
BOOLEAN?, NULL?, LIST?, PAIR?, CONS, et cetera for idiosyncratic
purposes.  As long as such *conventions* can be implemented in a standard
Scheme, there is no creative restriction and many people are saved from
needless confusion. 

I would be very interested in deep reasons why such confusion should be

Jinx, if you can explain to my simple self why you cannot redefine a
scheme implementation which follows the standard to do what you want in
this case, please do so.  If not, I request that you remove your

-Ken Dickey