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bounded, infinite ranges?



   ...My reason: a range is over floats, yes?  Therefore no
   enumerative approach would terminate (any range has an infinite
   number of elements), even if one was provided.

Huh?  Floats are not reals -- after all, they're represented finitely.

As for the meaning of IEEE infinity, it is not really infinity either:
it stands for all numbers too large to represent in a given floating
type.

   These values that sit outside the system, "top" and "bottom" values
   are usually very important to a program.  IMHO, it was unfortunate
   that they were left out of the Dylan language spec.

I agree.  Dylan appears to use #f as a substitute for a void value in
some cases, e.g. while, until, bind with no forms.  This, and the fact
that ANY non-#f value is true, seem to be residual Lispisms.

Note that adding void to the possible returns of a function increases
function-return overhead, since of course you have to find some place
for the necessary bits....  (If you do it by some control convention,
there is still some overhead somewhere.)

	-s