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From: Zachary Ware <zachary.ware+pylist@gmail.com>
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Subject: Re: How are you supposed to define subclasses in C?
Date: Thu, 21 Apr 2016 11:39:09 -0500
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Xref: csiph.com comp.lang.python:107460

On Thu, Apr 21, 2016 at 11:35 AM, Random832 <random832@fastmail.com> wrote:
> I was trying to write a proof of concept on including descriptors (e.g.
> a "sys.recursionlimit" instead of set/get methods) in the sys module,
> and couldn't figure out how to "properly" define a type using
> PyType_FromSpecWithBases. Everything I tried just segfaulted. I ended up
> just calling PyObject_CallFunctionObjArgs((PyObject *)&PyType_Type, ...)
> but I assume there's a better way to do it. I couldn't find any examples
> or tutorial.

Have a look at https://hg.python.org/cpython/file/default/Modules/xxsubtype.c

-- 
Zach