On Wed, 30 Dec 2015 17:31:11 -0700, Ian Kelly wrote:
>> In any case, I thought that class attributes were, in fact, items of
>> __dict__?
>
> That's correct, but as I said in my previous message, self.attrs and
> self.attrs.__dict__ are two different dicts, and you're confusing one
> for the other. Maybe this will be illuminating:
>
>>>> class mydict(dict): pass
> ...
>>>> md = mydict()
>>>> md['foo'] = 42 # Set an item in md
>>>> md['foo'] # 'foo' exists as an item
> 42
>>>> md.foo # but not as an attribute
> Traceback (most recent call last):
> File "<stdin>", line 1, in <module>
> AttributeError: 'mydict' object has no attribute 'foo'
>>>> md.__dict__['foo'] # and it's not in md.__dict__
> Traceback (most recent call last):
> File "<stdin>", line 1, in <module>
> KeyError: 'foo'
>>>> md.bar = 43 # Set an attribute on md md.bar # 'bar' exists as an
>>>> attribute
> 43
>>>> md.__dict__['bar'] # and it's in md.__dict__
> 43
>>>> md['bar'] # but it's not in md itself
> Traceback (most recent call last):
> File "<stdin>", line 1, in <module>
> KeyError: 'bar'
>
> And to hopefully drive the point home:
>
>>>> md.items()
> [('foo', 42)]
>>>> md.__dict__.items()
> [('bar', 43)]
Okay, I think I got an important point that you said earlier but
I didn't get the full ramifications thereof:
class md (... more about this ...):
pass
md is a class that has an dictionary attribute __dict__:
- md['level1'] puts attributes in md
- md.level2 puts attributes in md.__dict__
is that correct?
Now, as to the superclass, if that's, say, object, then
it has two levels:
md -> object (containing a dict)
if the superclass is dict, then it only has one level:
md -> dict
I'll have to look at my methods again with those understandings.
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