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*To*: macrakis@osf.org*Subject*: Re: bounded, infinite ranges?*From*: andyw@ibeam.ht.intel.com (Andy Wilson)*Date*: Tue, 20 Oct 92 14:16 PDT*Cc*: info-dylan@cambridge.apple.com

-------------------------------------------------------------- ...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. --------------------------------------------------------------- Absolutely right -- which is why I originally asked the question about ranges where one of the bounds is infinity. Actually, there's a much more mundane question about ranges with float bounds: what is the (size) of such a range, which is defined in the April '92 book as an integer. Naively, one might assume that (size range) could be defined as (/ (- (top range) (bottom range)) (by range)). However, since floats are in fact represented finitely, if the "by:" step size for range is sufficiently small there might well be too few allowable bit patterns to represent the theoretical number of intervals in the range. You could define away this problem by requiring by:, from:, up-to: and through: to be rational, thus making the size calculation exact. BTW, I'd still like an answer on the other question about Dylan syntax for infinities and NaN's. Any takers? atw

**Follow-Ups**:**bounded, infinite ranges?***From:*Stavros Macrakis <macrakis@osf.org>

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