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On Sun, 23 Oct 2005, [ISO-8859-1] Jens Axel Søgaard wrote:
>Say I want to write my own mathematical function and need to return NaN?
>E.g.
>
> (if <check-arguments>
> <calculate-result>
> #<not-a-number>
Okay, how about a library function:
(define NaN (lambda()
"return a NaN for use in other functions,
because there is no read/write syntax for NaN."
(/ 0.0 0.0)))
then you can write:
(if <check-arguments>
<calculate-results>
(NaN))
So your code is clear and readable, and yet you
don't have a read/write syntax that makes it unclear
whether read is failing or just reading an error.
Bear