The rationale discusses NaN, but I think the solution that
0/0. = 0/0. is wrong.  I think it is important to be compatible
with IEEE, and that 0/0. be the same as NaN.

The Kawa solution (which I think is the right one):

(define NaN ...)
(= NaN NaN) => #f
(eq? NaN NaN) => #t
(eqv? NaN NaN) => #t
(equal? NaN NaN) => #t

This may technically violate R5RS, but I think it's the
best choice if we want to be compatible with IEEE, which
think we do.
--
	--Per Bothner
xxxxxx@bothner.com   http://per.bothner.com/