Re: [Tutor] object's attributes

[Alan Gauld]

"spir" <denis.s...@free.fr> wrote
Can someone explain the following?

Not really an explanation but I did notice when repeating your
experiment that your class instance has a __dict__ attribute
but object does not. The new attribute a is apparently
located in the dict.

class C(object): pass
...
o = object()
c = C()
c.a = 6
dir(c)
['__class__', '__delattr__', '__dict__', '__doc__', 
'__getattribute__', '__hash_
_', '__init__', '__module__', '__new__', '__reduce__', 
'__reduce_ex__', '__repr_
_', '__setattr__', '__str__', '__weakref__', 'a']
dir(o)
['__class__', '__delattr__', '__doc__', '__getattribute__', 
'__hash__', '__init_
_', '__new__', '__reduce__', '__reduce_ex__', '__repr__', 
'__setattr__', '__str_
_']

print c.__dict__
{'a': 6}

And the dict exists before the new attribuite is created:

d = C()
dir(d)
['__class__', '__delattr__', '__dict__', '__doc__', 
'__getattribute__', '__hash_
_', '__init__', '__module__', '__new__', '__reduce__', 
'__reduce_ex__', '__repr_
_', '__setattr__', '__str__', '__weakref__']

Does that help? I don't know.
Why does a class inheriting from object acquire a dict when object 
doesn't have one?

I'm sure somebody can explain but its not me...

Alan G.


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