Treffer: Generic Co- and Contravariance in Visual Basic 2010.

The article discusses the features of the Visual Studio 2010, the generic covariance (co-) and contravariance. It says that generic co- is a language feature that works for the interfaces. It mentions that contravariance allows safe casting of an IComputer(Of Base) into any IComparer(Of Derived). Meanwhile, knowing what triggers ambiguity and how the Visual Basic computer handles it is important since co- and contravariance launch ambiguity in member lookup.