Rich Comparisons Gotcha
jstroud at mbi.ucla.edu
Mon Dec 8 09:10:20 CET 2008
Robert Kern wrote:
> James Stroud wrote:
>> I think it skips straight to __eq__ if the element is not the first in
>> the list.
> No, it doesn't skip straight to __eq__(). "y is 1" returns False, so
> (y==1) is checked. When y is a numpy array, this returns an array of
> bools. list.__contains__() tries to convert this array to a bool and
> ndarray.__nonzero__() raises the exception.
> list.__contains__() checks "is" then __eq__() for each element before
> moving on to the next element. It does not try "is" for all elements,
> then try __eq__() for all elements.
Ok. Thanks for the explanation.
> > That no one acknowledges this makes me feel like a conspiracy
> > is afoot.
> I don't know what you think I'm not acknowledging.
Sorry. That was a failed attempt at humor.
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