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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Fri, 20 May 2011 11:59:44 -0600
Subject: Re: hash values and equality
To: Python <python-list@python.org>
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On Fri, May 20, 2011 at 10:36 AM, Chris Kaynor <ckaynor@zindagigames.com> wrote:
> I think the question was: can this dummy code ever produce a set containing
> less then itemCount items (for 0 < itemCount < 2**32)?

In CPython, no.  Even when you get a hash collision, the code checks
to see whether the hashes are actually equal before it calls the rich
comparison, the former check being a much faster operation since the
hash values are cached.

I'm not sure whether this can be counted on for all Python
implementations, though.