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Re: bignum branch

From: Paul Eggert
Subject: Re: bignum branch
Date: Fri, 3 Aug 2018 14:02:04 -0700
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1

On 08/03/2018 01:17 PM, Tom Tromey wrote:
> I'm not sure what the semantics of NaN comparison are in Emacs.  In
> particular, this doesn't really make sense to me:
>     (> 0 0.0e+NaN) => nil
>     (< 0 0.0e+NaN) => nil
>     (min 0 0.0e+NaN) => 0.0e+NaN
>     (min 0.0e+NaN 0) => 0.0e+NaN
>     (max 0 0.0e+NaN) => 0.0e+NaN
>     (max 0.0e+NaN 0) => 0.0e+NaN

NaNs never compare numerically equal to, less than, or greater than any
other floating-point value, even other NaNs. This is part of the IEEE

min and max propagate any NaNs they find.

By the way, we've changed master so that eql now looks at NaN's
significands. That is, (eql x y) now returns t if x and y are NaNs
containing identical significands.

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