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From: Dave Angel <davea@davea.name>
Subject: Re:intersection, union, difference, symmetric difference for dictionaries
Date: Tue, 25 Feb 2014 16:35:50 -0500 (EST)
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Xref: csiph.com comp.lang.python:67062

 mauro <mauro@gmail.com> Wrote in message:
>  Dictionaries and sets share a few properties:
> - Dictionaries keys are unique as well as sets items
> - Dictionaries and sets are both unordered
> - Dictionaries and sets are both accessed by key
> - Dictionaries and sets are both mutables
> 
> So I wonder why operations such us intersection, union, difference, 
> symmetric difference that are available for sets and are not available 
> for dictionaries without going via key dictviews. 
> 

I certainly wouldn't be able to guess what they should be defined
 to do, since there are several equally obnoxious possibilities.
 

For instance,  take union for example.  What should be the result
 when you union two dicts that have the same key but different
 values for that key?


-- 
DaveA