python, please,what is the difference between one.__class__ and one().__class__?

topheraholic · 11-07-2009, 08:38 AM

the script is this:

Code:

class one:
   pass
class two(one):
   pass

i got an error when i ran

Code:

two.__class__

who can tell me why?
what is the difference between

Code:

object.__class__ and object().__class__

thanks very much!

Hko · 11-08-2009, 05:49 AM

Quote:

Originally Posted by topheraholic

what is the difference between

Code:

object.__class__ and object().__class__

thanks very much!

object is a class.
object() is an instance of the class 'object'.

object.__class__ is referring to the class of the object class.
object().__class__ is referring to the class of an instance of the 'object' class.

So, object().__class__.__class__ is the same as object.__class__

Quote:

Originally Posted by topheraholic

i got an error when i ran

Code:

two.__class__

who can tell me why?

two is a class. So you might expect two.__class__ to be: <type 'classobj'>.

But then two.__class__.__class__ would be: <type 'classobj'> too.

And two.__class__.__class__.__class__.__class__.__class__ too. This never ends. That is why, I suppose, <class>.__class__ is not defined.