// CS0314: The type `U' cannot be used as type parameter `T' in the generic type or method `A<T>'. There is no boxing or type parameter conversion from `U' to `System.IComparable' // Line: 13 using System; class A<T> where T: IComparable { } class B<U,V> where V: A<U> { } class Driver { public static void Main () { } }