Re: [Scheme-reports] Formal Comment: R7RS 'eqv?' cannot be used for reliable memoization

[Alex Shinn <alexshinn@x>]

On Fri, Nov 23, 2012 at 2:25 AM, Mark H Weaver <mhw@x> wrote:

John Cowan <cowan@x> writes:

> How about this compromise:  simply remove the clause defining `eqv?` on
> non-IEEE flonums?  It is arguably not a proper domain for standardization
> anyway, since there are no such implementations today.  That would allow
> future implementations to return `#t` or `#f` at their discretion.

This would be *vastly* better than the current situation.  If it's the
best we can hope for, then _please_ do this.  This would make it very
likely that implementations would correctly extrapolate the definition
of 'eqv?' to other representations.

This has been mentioned multiple times, and I think

would be vastly inferior to the current situation.  It

means that eqv? is basically unspecified on inexacts -

you couldn't even rely on (eqv? 1.0 1.0) => #t.  It's

also semantically different from what we voted on,

meaning it would require a re-vote, whereas my proposal

isn't.

-- 

Alex

_______________________________________________
Scheme-reports mailing list
Scheme-reports@x
http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports