C API []-style access to instance objects

[André Malo]

* williams.jasonscott at gmail.com wrote:

> Hi,
> 
> I am having trouble figuring out how to set up an object to be
> scriptable through the C API.  An example of what I am attempting to
> do:
> 
>>>> obj = foo.Foo()
>>>> obj["key"]
> Traceback (most recent call last):
>   File "<stdin>", line 1, in ?
> TypeError: unsubscriptable object
>>>>
> 
> I've tried defining __getitem__ as a method, but that hasn't worked.
> Is there a tp_field that I am failing to understand, something like
> tp_iter and tp_iternext?

tp_as_mapping is what you're looking for. It takes the pointer to another
structure: PyMappingMethods.

You might want to try the modulator script (comes with the source
distribution of python), which generates some of the basic type methods for
you. It's a bit old, but gives a good start.

nd
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