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card
10 New Member
Hey Everyone,

I have a question about new types in Python. *Just finished reading up and
trying a few things out, but I'm a little confused about one thing. *When
declaring a new type, we basically have two new structures. *One is the per
instance structure (your PyObject structure), which is basically an expansion
of the PyObject structure. *At the beginning of that structure is the macro
declaration of PyObject_HEAD which contains the reference counter and a
pointer to the new type which is a structure of _typeobject. *Then for your
new type (i.e. your _typeobject structure) there is a place holder for the
size of your per instance PyObject structure along with all the necessary
function pointers your new type will support. *My question is this: *Where
and when does the pointer in your per instance PyObject structure get set? *
How does the interpreter know that your PyObject structure is related to your
PyTypeObject structure? *Since your PyObject structure naming convention is
not tied to your PyTypeObject name, how are the two associated? *I see how
your type is statically instantiated in the initialization, but I don't see
where your per instance PyObject is related to it? *Is it simply that the two
structures co-exist in the same module? *It's just one of those nagging questions. Thanks.
Jun 14 '07 #1
1 969
bartonc
6,596 Recognized Expert Expert
Hi, card.
Now this question is nagging me.
I'll look into it and let you know when/if I find the answer.

Sorry to be of little help at the moment.

Thanks for you contributions to the Python Forum.
Jun 15 '07 #2

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