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Is exact 0 "stronger" than inexact 0.0?

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.

   (* 0 +inf.0)                           ==>  +nan.0
   (/ 0 0.0)                              ==>  unspecified
   (/ 0.0 0)                              ==>  +nan.0
   (/ 0.0 0.0)                            ==>  +nan.0

Why is only (/ 0 0.0) out of this set unspecified?

How should (/ 0 0) behave?


The description of `+' and `*' says:

    If any of these procedures are applied to mixed non-rational real
    and non-real complex arguments, they either report a violation of
    an implementation restriction or return an unspecified number.

The only non-rational real numbers in current implementations are
+inf.0 and -inf.0.  Is this what was intended?

If so, calling them infinities would be less cryptic.

Shouldn't that sentence also appear in the description of `-' and `/'?

It allows return of "an unspecified number."  Does that allow a NaN to
be returned?