[Tutor] slots and inheritance - a bit more

[Arthur Siegel]

Tim writes -

> Slots are inherited.  What have you seen that made you believe they're not
> inherited?
>
> >>> class A(object):
> ...     __slots__ = 'a'
> ...
> >>> class B(A):
> ...     pass
> ...
> >>> b = B()
> >>> b.a = 12
> >>> b.x = 42
> >>> b.a
> 12
> >>> b.x
> 42
> >>> b.__dict__  # only 'x' is in the dict; 'a' is stored in inherited slot
> {'x': 42}
> >>>

Helps.

But the *functionality* of slots is not inherited - unless I kill B's
__dict__.  Correct? If so, is that doable?


> BTW, note that __slots__ are really an optimization gimmick.  There's no
> reason to bother with them unless you have a great many instances of some
> class and need to reduce memory use.  Then they can help, but then you
also
> have to live with the restrictions the use of __slots__ impose.

I kind of thought the restriction - as in object.kolor = "blue" when you
meant
object.color= "blue" was of the essence of slots.  But if you mean the
multi-heritance restriction - yes.  Happens to be a deal killer in my case.

Art