About "Object in list" expression

Mirons ilmirons at gmail.com
Mon Nov 2 11:59:15 CET 2009

On 2 Nov, 11:46, Jon Clements <jon... at googlemail.com> wrote:
> On Nov 2, 10:41 am, Mirons <ilmir... at gmail.com> wrote:
> > Hi everybody! I'm having a very annoying problem with Python: I need
> > to check if a (mutable) object is part of a list but the usual
> > expression return True also if the object isn't there. I've
> > implemented both __hash__ and __eq__, but still no result. what does
> > "in" implementation use for comparison (Python is 2.6)?
> It would help showing an example...

I just solved the problem! (Sorry for the bother). It was a matter of
inplementation. It's __eq__ that is called for checking instances in
list but I had implemented two version of __eq__ in different parts of
code and the interpreter chose the wrong one. Excuse me again for the

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