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Fool Python class with imaginary members (serious guru stuff inside)

Steven D'Aprano steve+comp.lang.python at pearwood.info
Thu Sep 20 15:15:06 EDT 2012 
On Thu, 20 Sep 2012 06:52:07 -0700, Jure Erznožnik wrote:

> I'm trying to create a class that would lie to the user that a member is
> in some cases a simple variable and in other cases a class. The nature
> of the member would depend on call syntax like so: 
> 1. x = obj.member #x becomes the "simple" value contained in member 
> 2. x = obj.member.another_member #x becomes the "simple" value
> contained in first member's another_member.

Why do you hate your users so much that you want to cause them enormous 
difficulty with perfectly reasonable code like this?

tmp = obj.member
x = tmp.another_member


> So the first method "detects" that we only need a simple value and
> returns that.

Fortunately that is impossible without nasty bytecode or AST hacks. Thank 
the stars that Python doesn't allow anything as badly designed as this!



-- 
Steven
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