It seems that a class that implements an interface cannot rely on inherited methods to have implemented some of the methods already. Boo insists that all the methods are declared and implemented in the actual class which implements the interface. Whereas C# (and common sense?) says that if a class inherits from a class that already implements all the methods, then the contract is satisfied. The example below fails to instantiate B, the error message is about B not implementing an interface etc. In either case, though, its just wrong to say that class B doesn't implement IDo. ---------------------------------- import System interface IDo: def Do1() def Do2() class A: def Do1(): pass class B(A, IDo): #def Do1(): # Shouldn't need to implement again since

1. pass # Class B inherits Do1() from class A def Do2(): pass

b = B() # FAILS since B doesn't implement Do1() ---------------------------------- See Google thread http://groups.google.com/group/boolang/browse_thread/thread/a9446572632cea8d?hl=en Doug H confirms this bug.