[Python-Dev] Class Methods

[Thomas Heller]

> >>>>> "GvR" == Guido van Rossum <guido@digicool.com> writes:
> 
>     GvR> Let x be an object, C its class, and M C's class.  So,
> 
>     |   x.__class__ is C
>     |   C.__class__ is M
> 
>     GvR> Then x's methods are described in C.__dict__, and C's methods
>     GvR> are described in M.__dict__.
> 
>     GvR> The problem is that if you write C.spam, there could be two
>     GvR> spams: one in C.__dict__, one in M.__dict__.  Which one to
>     GvR> use?
> 
[Barry wrote]
> If you use naming to generally distinguish, and have a lookup chain
> that first found it in C.__dict__ and then looked in M.__dict__, you
> could control what happens when the name is in both dicts by using a
> more explicit lookup, e.g. C.__dict__['meth']
> vs. C.__class__.__dict__['meth']
> 

Couldn't be C.__class__.meth be used?

> But maybe that's too ugly.
>     
>     GvR> How does Smalltalk resolve this?
I'm walking on thin ice here (maybe I should better try it out),
but IIRC Smalltalk requires to explicit:

    self class method;
or
    self method;

> Another question: presumably when I write
> 
>     class Foo: pass
> 
> Foo is implicitly given the built-in metaclass M, but say I wanted to
> define a class Foo with a different metaclass, how would I spell this?
> I think at one point I suggested a semi-ugly syntactic hack, where
> `class' was actually a namespace and you could add new metaclasses to
> it.  So you could write something like
> 
>     class.WeirdClass Foo: pass
> 
> and now Foo's metaclass would be WeirdClass.
Thin ice again I'm on here (even more), but I have the impression
that creating a class Point in Smalltalk _automatically_ creates
two classes: Point and PointClass. The latter is normally hidden
(but contains the class methods of Point as instance methods).

Thomas