[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Scheme-reports] EQV? on numbers should be based on operational equivalence

On Tue, May 8, 2012 at 8:42 AM, Mark H Weaver <mhw@x> wrote:
> John Cowan <cowan@x> writes:
>> Mark H Weaver scripsit:
>>> In particular, on platforms with signed zeroes, the R7RS should mandate
>>> that (eqv? 0.0 -0.0) => #false.
>> R6RS mandates that, but R7RS currently leaves it unspecified.
> How would you suggest implementing memoization in a portable R7RS
> program?

It must be unspecified in R7RS because R7RS
does not require that implementations distinguish
between 0.0 and -0.0, nor that they provide +inf.0
or -inf.0.


Scheme-reports mailing list