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Where does a class closure live?

Consider:

### Function closure example

def outer(s):
.... def inner():
.... print s
.... return inner
....
>>f = outer(5)
f()
5
>>dir(f)
['__call__', '__class__', '__delattr__', '__dict__', '__doc__',
'__get__', '__getattribute __', '__hash__', '__init__', '__module__',
'__name__', '__new__', '__reduce__', '__reduce_ex__' , '__repr__',
'__setattr__', '__str__', 'func_closure', 'func_code', 'func_defaults' ,
'func_dict', 'func_doc', 'func_globals', 'func_name']

### Class instance closure example
>>def outer2(s):
.... class Inner(object):
.... def __call__(self):
.... print s
.... return Inner()
....
>>f = outer2(10)
f()
10
>>dir(f)
['__call__', '__class__', '__delattr__', '__dict__', '__doc__',
'__getattribute __', '__hash__', '__init__', '__module__', '__new__',
'__reduce__', '__reduce_ex__' , '__repr__', '__setattr__', '__str__',
'__weakref__']

##### Class closure example
>>def outer3(s):
.... class Inner(object):
.... def __call__(self):
.... print s
.... return Inner
....
>>F = outer3(15)
f = F()
f()
15
>>dir(F)
['__call__', '__class__', '__delattr__', '__dict__', '__doc__',
'__getattribute __', '__hash__', '__init__', '__module__', '__new__',
'__reduce__', '__reduce_ex__' , '__repr__', '__setattr__', '__str__',
'__weakref__']
Now the closure for the function live in func_name. I've even done the
exercise where I build a dummy inner function that returns its closed
variable, so that I can use that thing to reach through "cells" and
check out the variables living in the closure object. Where are the
closure variables for the class instance, and the class? Can I get my
hands on them in Python?
-Gerard
Dec 6 '06 #1
0 1085

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