Re: float("nan") in set or as key

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Date	Sun, 29 May 2011 10:32:43 +1000
Subject	Re: float("nan") in set or as key
From	Chris Angelico <rosuav@gmail.com>
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On Sun, May 29, 2011 at 10:28 AM, Albert Hopkins <marduk@letterboxes.org> wrote:
> This is the same nan, so it is equal to itself.
>

Actually, they're not. But it's possible the dictionary uses an 'is'
check to save computation, and if one thing 'is' another, it is
assumed to equal it. That's true of most well-behaved objects, but nan
is not well-behaved :)

Chris Angelico

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Re: float("nan") in set or as key Chris Angelico <rosuav@gmail.com> - 2011-05-29 10:32 +1000
  Re: float("nan") in set or as key Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-05-29 08:51 +0000

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