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Re: My ideas about infinity in Scheme (revised)
| Date: Sat, 21 May 2005 14:39:59 -0700
| From: Alef Null Petrofsky <al@xxxxxxxxxxxxx>
| > From: Aubrey Jaffer <agj@xxxxxxxxxxxx>
| > How about "1/0." and "-1/0."?
| Something I'd just like to throw out there is that one can represent
| the inexact floating-point entities "NaN" and positive and negative
| "infinity" without extending the r5rs BNF at all, by using #i0/0,
| #i1/0, and #i-1/0.
Those would work.
The #e and #i prefixes are not one of the better Scheme inventions:
#e-5 puns 1#e-5; #i-1/0 suggests an imaginary infinity to
| (I implemented this for kawa back in 1998, but I don't know whether
| kawa still uses that notation.)
Kawa 1.7.90 accepts #i1/0, #i-1/0, and #i0/0; also #e1/0 and #e-1/0.
[but chokes on 1#.e-5]