Surprise using the 'is' operator

John Roth JohnRoth1 at jhrothjr.com
Tue Sep 26 08:59:05 EDT 2006


Antoon Pardon wrote:
>
> I find this a bit oddly worded. Now the "may always reuse" phrase
> suggests this is not an obligation and I can certainly understand
> that in the case of integers. But when you enumerate examples you
> include None and Booleans, creating the suggestion these don't
> have to be implemented as singletons either and that there can be
> more than one None, True and False object. Now I probably just
> misunderstand, but I'm wondering, is there somewhere in the language
> reference that specifies these have to be singletons?

Yes. The topic "The standard Type Hierarchy" in the
Language reference specifies this exactly.

John Roth
> 
> -- 
> Antoon Pardon




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