[Python-ideas] Why is nan != nan?

Stephen J. Turnbull stephen at xemacs.org
Sun Mar 28 10:04:08 CEST 2010

Bruce Leban writes:

 > (Personally, I would have made them non-hashable so you couldn't
 > accidentally stick one in a dict but that's another problem.)

No, it's not.  AIUI, that is one of the main issues that's being
discussed in this thread.  Most people seem reasonably satisfied with
other behavior, so the discussion bounces back and forth between
whether NaNs should be hashable (and, perhaps more often, whether they
should all be equal or not), and how any change in identity or
equality behavior might affect computations in existing programs.

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