What is wrong with this attempt to extend a Scala class that contains a vararg parameter

Question

class U(successors:U*) {}
class V(successors:U*) extends U(successors) {}

The second line doesn't compile. Type mismatch on the second occurrence of successors.

Answer 1

U* is converted to Seq[U]. Use,

class V(successors: U*) extends U(successors:_*) {}