Subj : Spidermonkey: Incorrect NaN comparison
To   : netscape.public.mozilla.jseng
From : Corey Murtagh <emonk@slingshot.co.nz.no.uce>
Date : Fri May 16 2003 05:59 pm

Trying this:

   print(Math.floor(undefined) + " " +
       Math.floor(undefined) == NaN)

produces:

   NaN false

So, it appears that NaN values returned by the Math functions are non 
comparable to the NaN constant.  According to E262-3 (section 8.5):

"... to ECMAScript code, all NaN values are indistinguishable from
each other."

I read this to mean that any of the 9007199254740990 (according to 
E262-3) possible NaN values should be equivalent.


-- 
Corey Murtagh
The Electric Monk
"Quidquid latine dictum sit, altum viditur!"

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