On Sat, 11 Apr 2009 03:01:48 -0700, Edd wrote:
> Yes I probably mean instance attributes. Forgive me, I am not
> particularly sure of the terminology. But your MyClass example, won't
> quite do what I want, as I'd like to be able to define instance
> attributes on top of instance attributes by assignment:
>
>>>> class MyClass(): pass
> ...
>>>> instance = MyClass()
>>>> instance.lasers.armed = True
> Traceback (most recent call last):
> File "<stdin>", line 1, in <module>
> AttributeError: MyClass instance has no attribute 'laser'
Ah, now it is more clear.
Okay, let's try this:
>>> class C(object):
... def __getattr__(self, name):
... # Only called if self.name doesn't exist.
... inst = self.__class__()
... setattr(self, name, inst)
... return inst
...
>>> c = C()
>>> c.x.y.z = 45
>>> c.__dict__
{'x': <__main__.C object at 0xb7c3b78c>}
>>> c.x.__dict__
{'y': <__main__.C object at 0xb7c3b7ec>}
>>> c.x.y.z
45
--
Steven
--
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