Hashability of classes, old and new

Josiah Carlson jcarlson at nospam.uci.edu
Mon Feb 16 20:10:33 CET 2004


> So, despite c1 equals c2, they create two different entries in a
> dictionary.  I thought that this is such an inconsistency that was the
> reason behind requiring an explicit `__hash__' for old-style classes.
> So, it seems I was not thinking right, there is something which escapes
> my understanding.  Would some kind soul help mine? :-)

When two objects have different hashes, they are not required to be 
compared when inserted into a dictionary.  They may be compared, if two 
hashes drop the objects into the same bin.

  - Josiah



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