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Date: Tue, 4 Sep 2012 23:40:33 -0700
Subject: Re: is implemented with id ?
From: Benjamin Kaplan <benjamin.kaplan@case.edu>
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On Tue, Sep 4, 2012 at 11:30 PM, Franck Ditter <franck@ditter.org> wrote:
> Hi !
> a is b <==> id(a) == id(b) in builtin classes.
> Is that true ?
> Thanks,
>
>     franck

No. It is true that if a is b then id(a) == id(b) but the reverse is
not necessarily true. id is only guaranteed to be unique among objects
alive at the same time. If objects are discarded, their ids may be
reused even though the objects are not the same.