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inheriting from C types

Renzo Tomaselli renzo.tomaselli at tecnotp.it
Tue Jul 16 14:05:59 EDT 2002 
Hi all,
	I'm looking at tips & tricks about inheriting from a C type. It works
(almost), but from any derived class I'm not able to see any base
class method.
Say I implemented a C-type "ype" having
Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE flags as well as tp_dealloc,
tp_getattr slots.
Allocators, constructors etc. are usual defaults.
Now, in Python:

import ype
class k(ype.ype):
	pass
k1 = k()

I cannot see/invoke any method on base class ype from k1, while I can
see all of them after direct creation of a base instance, say k2 =
ype.ype().
I noticed that invoking any such method on k1 ends up in calling
PyObject_GetAttr, which finds slot tp_getattro on the derived class k;
this in turns calls PyObject_GenericGetAttr which fails.
Almost surprisingly there is no attempt to climb the base class
hierarchy.
Any help is appreciated,

Renzo Tomaselli
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