On 05/02/2013 07:57 AM, Barry Warsaw wrote:
On May 01, 2013, at 11:54 AM, Larry Hastings wrote:
On 04/30/2013 11:29 PM, Ethan Furman wrote:
On 04/30/2013 11:18 PM, Barry Warsaw wrote:
On Apr 28, 2013, at 11:50 PM, Ethan Furman wrote:
But as soon as:
type(Color.red) is Color # True
type(MoreColor.red) is MoreColor # True
then:
Color.red is MoreColor.red # must be False, no?
If that last statement can still be True, I'd love it if someone >>> showed me
how.
class Foo:
a = object()
b = object()
class Bar(Foo):
c = object()
Foo.a is Bar.a
True
Wow. I think I'm blushing from embarrassment.
Thank you for answering my question, Barry.
Wait, what? I don't see how Barry's code answers your question. In his
example, type(a) == type(b) == type(c) == object. You were asking "how can
Color.red and MoreColor.red be the same object if they are of different
types?"
p.s. They can't.
Sure, why not? In "normal" Python, Bar inherits a from Foo, it doesn't define
it so it's exactly the same object. Thus if you access that object through
the superclass, you get the same object as when you access it through the
subclass.
So Foo.a plays the role of Color.red and Bar.a plays the role of
MoreColor.red. Same object, thus `Foo.a is Bar.a` is equivalent to `Color.red
is MoreColor.red`.
So you're saying Color.red and MoreColor.red are the same object. Which
means they have the same type. But in Ethan's original example above,
type(Color.red) == Color, and type(MoreColor.red) == MoreColor. Those
are different types.
So, for the second time: How can Color.red and MoreColor.red be the same
object when they are of different types?
p.s. They can't.
//arry/
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