Annoying behaviour of the != operator

Christopher Subich spam.csubich+block at
Wed Jun 8 22:45:20 CEST 2005

Peter Hansen wrote:

 > I can see only one comment that seems to describe that situation, 
where it refers to "IEEE 754 floating point numbers do not satisfy [== 
being the complement of !=]".
 > (Though that may be justification enough for the feature...)

To my naive eye, that possibility seems like justification for the 
language to not -enforce- that (not (a == b)) == (a != b), but for the 
vast majority of cases this is true.  Perhaps the language should offer 
the sensible default of (!=) == (not ==) if one of them but not the 
other is overriden, but still allow overriding of both.

This would technically break backwards compatibilty, because it changes 
default behavior, but I can't think of any good reason (from a python 
newbie perspective) for the current counterintuitive behavior to be the 
default.  Possibly punt this to Python 3.0?

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