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To: python-list@python.org
From: Peter Otten <__peter__@web.de>
Subject: Re: Any built-in ishashable method ?
Date: Sat, 19 Jan 2013 09:49:13 +0100
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Xref: csiph.com comp.lang.python:37074

Dave Angel wrote:

> On 01/18/2013 07:06 AM, Peter Otten wrote:
>> Jean-Michel Pichavant wrote:
>>
>>> That brings me to another question, is there any valid test case where
>>> key1 != key2 and hash(key1) == hash(key2) ? Or is it some kind of design
>>> flaw ?
>>
>> I don't think there is a use case for such a behaviour other than
>> annoying your collegues ;)
>>
> 
> Beg to differ.  Nothing wrong with getting the same hash on objects that
> compare different.  It's called a hash collision, and is quite common,
> especially in large collections.

Of course.

> The problem is the converse of this, where the objects compare equal,
> but they have different hashes.

And that I read because my expectations won over the actual text.