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*To*: labrea!common-lisp%sail@labrea.Stanford.EDU*Subject*: LEAST-POSITIVE-<mumble>-FLOAT*From*: Jon L White <edsel!jonl@labrea.Stanford.EDU>*Date*: Fri, 22 Jan 88 22:15:21 PST

Does anyone care what values these "constants" actually take on? that is, does anyone use then in any context other than test suites? CLtL p231 says that this number should be the "number closest in value to (but not equal to) zero provided by the implementation." In those implementations supporting IEEE-like denormalized numbers, a question arises: are denormalized numbers "provided", in the sense required? Of the four such implementations I've checked, half set this constant to the least normalized number, and half set it to the least denormalized number. Supporting the former is the fact that IEEE hardware, when traps are enabled, will signal an underflow trap whenever a result would be less than the least normalized number. Supporting the latter is the fact that under at least mode of operation of the hardware, denormalized numbers are "provided" by the implementation. -- JonL --

**Follow-Ups**:**LEAST-POSITIVE-<mumble>-FLOAT***From:*Robert A. Cassels <Cassels@stony-brook.scrc.symbolics.com>

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