[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Scheme-reports] [Chicken-hackers] [PATCH] Omit warning about exact fractions when asked for an inexact value
- To: chicken-hackers <chicken-hackers@x>, Scheme Reports <scheme-reports@x>
- Subject: Re: [Scheme-reports] [Chicken-hackers] [PATCH] Omit warning about exact fractions when asked for an inexact value
- From: John Cowan <cowan@x>
- Date: Fri, 23 Mar 2012 00:16:00 -0400
- In-reply-to: <20120322200157.GD19410@frohike.homeunix.org>
- References: <20120321213554.GK882@frohike.homeunix.org> <20120321221305.GC10202@mercury.ccil.org> <20120322114842.GA19410@frohike.homeunix.org> <20120322141310.GB21494@mercury.ccil.org> <20120322142452.GB19410@frohike.homeunix.org> <20120322150530.GD21494@mercury.ccil.org> <20120322151406.GC19410@frohike.homeunix.org> <20120322200157.GD19410@frohike.homeunix.org>
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
_______________________________________________
Scheme-reports mailing list
Scheme-reports@x
http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports