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Re: [Scheme-reports] [Chicken-hackers] [PATCH] Omit warning about exact fractions when asked for an inexact value

Peter Bex scripsit:

> According to the R7RS BNF, #e+inf.0 is actually valid numerical syntax,

Yes, you're right.  I shouldn't have said "syntax error".

> It's unclear to me whether (string->number "#e+inf.0") should
> return #f or raise an error.  The syntax is valid, but the question
> is nonsense: "give me an exact value of infinity".

In all my Schemes in which reading #e+inf.0 raises an error, using
string->number returns #f.  Only ones where #e+inf.0 returns +inf.0
do otherwise.

> But when you realize (eqv? +nan.0 +nan.0) is unspecified (section 6.1),

I wouldn't assume that's stable.

John Cowan              http://www.ccil.org/~cowan      cowan@x
Would your name perchance be surname Puppet, given name Sock?
                --Rick Moen

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