Re: [Scheme-reports] ballot question #229: EQV? and NaN
John Cowan 30 Sep 2011 06:05 UTC
Alex Shinn scripsit:
> On Fri, Sep 30, 2011 at 9:44 AM, Alex Shinn <alexshinn@gmail.com> wrote:
> >
> > By all means, but the ballot item was unclear and
> > will require a re-vote. In the meantime, the draft
> > we submit with the call for formal comments will
> > need to revert to either R5RS (unspecified) or R6RS.
>
> Sorry, still catching up on this. The R5RS description
> of `eqv?' is completely unambiguous in requiring the
> "different" semantics.
Well, presuming that (= +nan.0 x) is #f for all x.
> R6RS loosened the semantics slightly to make NaN
> `eqv?' comparisons unspecified.
(eqv? nan nan) and (eqv? nan nan2) are unspecified, but
(eqv? nan not-nan) is specified as #f.
--
He played King Lear as though John Cowan <cowan@ccil.org>
someone had played the ace. http://www.ccil.org/~cowan
--Eugene Field
_______________________________________________
Scheme-reports mailing list
Scheme-reports@scheme-reports.org
http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports