NaN doesn't test as == anything, even another NaN.

I was wondering: 
unless ($x <= $inf) { print "\$x is definitely a NaN\n" }
else { print "\$x is definitely NOT a NaN\n" }

[download]
Is that reliable ? ... assuming, of course, that $inf is in fact + infinity, and that there are no bugs present.
Seems to me that ought to be good enough.

Cheers,
Rob

In reply to Re^2: Answer: How do I create/detect/handle Infinity? by syphilis
in thread How do I create/detect/handle Infinity? by jdporter

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