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Date: Sat, 4 Jun 2011 06:35:12 +1000
Subject: Re: float("nan") in set or as key
From: Chris Angelico <rosuav@gmail.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:6968

On Sat, Jun 4, 2011 at 6:27 AM, Carl Banks <pavlovevidence@gmail.com> wrote=
:
> Really? =A0I am claiming that, even if everyone and their mother thought =
exceptions were the best thing ever, NaN would have been added to IEEE anyw=
ay because most hardware didn't support exceptions. =A0Therefore the fact t=
hat NaN is in IEEE is not any evidence that NaN is a good idea.

Uhh, noob question here. I'm way out of my depth with hardware floating poi=
nt.

Isn't a signaling nan basically the same as an exception? Which would
imply that the hardware did support exceptions (if it did indeed
support IEEE floating point, which specifies signalling nan)?

Chris Angelico