[Python-Dev] Semantic of isinstance

Greg Ewing greg.ewing at canterbury.ac.nz
Tue Jun 27 07:08:06 CEST 2006


Phillip J. Eby wrote:

> It's not inconsistent - isinstance() checks __class__ in *addition* to 
> type() in order to allow proxying tricks like lying about your 
> __class__.

If this is a deliberate feature, it's a bit patchy, because
it means the proxy can't lie about *not* being an instance
of its real type.

Perhaps Guido could clarify how much lying a proxy is
supposed to be able to get away with?

--
Greg


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