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Python C-API: how to define nested classes?

0 votes
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I'm currently writing a C extension module for python using the "raw" C-API. I would like to be able to define "nested classes" like in the following python code

class A: 
   class B: 
     def __init__(self): 
     self.i = 2 
     def __init__(self): 

     self.b = A.B() 
     a = A() 
     b = A.B() 
     print(a.b.i) 
print(b.i) 

How can I create such nested class with the C-API?

posted May 16, 2013 by anonymous

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2 Answers

0 votes

The nested class is just defining the scope of the nested class object that can be used solely in all outer proper classes.

It is not very useful in a language which supports dynamical run-time attribute binding in the instance level in the outer

answer May 16, 2013 by anonymous
0 votes

Assuming you really mean Python classes and not extension types, you might get away with defining them separately and then assigning

A.B = B

Recent Python versions added a __qualname__ attribute for classes that you might want to fix up in this case.

If you need better compatibility, consider writing your code in Cython.

answer May 17, 2013 by anonymous
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