[Zope-dev] Intercepting __getattr__ in a Python 2.3 old-style mixin class?

Hanno Schlichting hanno at hannosch.eu
Mon Nov 7 15:29:10 CET 2016

On Mon, Nov 7, 2016, at 14:01, Andreas Jung wrote:
> Python 2.7 is different because all classes are automatically new-style
> classes.
> In Python 2.7 you would have to overwrite __getattribute__() but I am on
> Python 2.3 here.

No :)

In Python 3 all classes are new-style classes. In Python 2 (including
2.7) you have to be explicit and either inherit from object (new-style)
or not (old-style).

In Python 2.7 you get:

>>> class A: pass
>>> class B(object): pass
>>> type(A)
<type 'classobj'>
>>> type(B)
<type 'type'>

In Python 3 both are of type 'type'.

And only new-style classes use '__getattribute__'. '__getattr__' is the
right approach for old-style classes in any Python 2 version, even in
Python 2.7.


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