extension modules in C for python, check for korrekt Object

[Michael Hudson]

Torsten Mohr <tmohr at s.netic.de> writes:

> Hi,
> 
> i write a set of extension modules for python in C.
> I also use some new types that i defined there.
> 
> At the moment i write some methods that expect some
> of these types as parameters.  I now want to check
> that the right types were given as parameters.
> 
> How can i do that?
> 
> PyArg_ParseTuple only checks that an object was
> given as parameter, but not its type.

It can check type, using the "O!" incantation.

If you're asking "how do I get hold of the type object I defined in
some other extension module?", then that's a good question.  One
approach is to use "CObjects":

    http://docs.python.org/ext/using-cobjects.html

> Do i need to check tp_name in the objects type?

This sounds fragile :-)

Cheers,
mwh

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