[IronPython] Problem with super

Christian Muirhead christian.muirhead at resolversystems.com
Thu Jul 12 12:35:33 CEST 2007

Anders M. Mikkelsen wrote:
> I have some problems getting 'super' working with IronPython.
> Running the following simple script:
>  class A:
>      def Foo(self):
>          pass
>  class B(A):
>      def Foo(self):
>          super(B, self).Foo()
>  B().Foo()
> yields:
>  TypeError: expected type, got classobj
> Any ideas?

Super only works for new-style classes - if you change class A to 
inherit from object super will work correctly.

Classes with no superclass list are created as old-style classes, which 
have slightly different semantics.

In general, all new classes you create should inherit from object, or 
some other built-in type, so that super, property and __metaclasss__ 
will work correctly for them. Old-style classes are only really kept for 
backwards compatibility, and I think they're going away at some version 
in the future - at which point "class A:" will define a normal new-style 


Christian Muirhead
Resolver Systems
christian.muirhead at resolversystems.com

Office address:     17a Clerkenwell Road, London EC1M 5RD, UK
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