// CS0508: `A<T>.B.getT()': return type must be `A<T>.B' to match overridden member `A<A<T>.B>.getT()' // Line: 10 abstract class A<T> { public abstract T getT (); public class B : A<B> { public override B getT () { throw new System.Exception ("The method or operation is not implemented."); } } }