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

Mark H Weaver scripsit:

> What I want, indeed what I *require*, is the ability to memoize
> procedures without having to worry that my code might produce the wrong
> answers on some future implementation of R7RS.

1) So use a memoization comparison function that handles NaN, negative
zero, and the infinities specially.

2) You can't be sure that an R7RS implementation will provide these

3) You can't be sure that an R7RS implementation will prove *any*
inexact numbers.

> Therefore, it appears likely that I will not be able to use R7RS.

So be it.

John Cowan    http://ccil.org/~cowan    cowan@x
SAXParserFactory [is] a hideous, evil monstrosity of a class that should
be hung, shot, beheaded, drawn and quartered, burned at the stake,
buried in unconsecrated ground, dug up, cremated, and the ashes tossed
in the Tiber while the complete cast of Wicked sings "Ding dong, the
witch is dead."  --Elliotte Rusty Harold on xml-dev

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