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Date: Thu, 13 Sep 2012 09:51:02 -0700 (PDT)
From: Volker Braun <vbraun.n...@gmail.com>
To: sage-devel@googlegroups.com
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Subject: Re: Caching considered controversial
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On Thursday, September 13, 2012 5:19:57 PM UTC+1, Nils Bruin wrote:

> sage: A==B 
> True 
> sage: hash(A) 
> 0 
> sage: hash(B) 
> 44546084519852655 


Really, the issue is that the objects violate the contract on 
object.__hash__():

"The only required property is that objects which compare equal have the 
same hash value"

http://docs.python.org/reference/datamodel.html


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On Thursday, September 13, 2012 5:19:57 PM UTC+1, Nils Bruin wrote:<br><blockquote class="gmail_quote" style="margin: 0;margin-left: 0.8ex;border-left: 1px #ccc solid;padding-left: 1ex;">sage: A==B
<br>True
<br>sage: hash(A)
<br>0
<br>sage: hash(B)
<br>44546084519852655&nbsp;</blockquote><div><br></div><div>Really, the issue is that the objects violate the contract on object.__hash__():</div><div><br></div><div>"The only required property is that objects which compare equal have the same hash value"<br></div><div><br></div><div>http://docs.python.org/reference/datamodel.html<br></div><div><br></div>
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