caseinherit.scala:2: error: case class `class B' has case ancestor `class A'. Case-to-case inheritance is prohibited. To overcome this limitation use extractors to pattern match on non-leaf nodes. case class B(y: Int) extends A(y) ^ caseinherit.scala:3: error: case class `object Bippy' has case ancestor `class A'. Case-to-case inheritance is prohibited. To overcome this limitation use extractors to pattern match on non-leaf nodes. case object Bippy extends A(55) ^ caseinherit.scala:6: error: case class `class Dingus' has case ancestor `class A'. Case-to-case inheritance is prohibited. To overcome this limitation use extractors to pattern match on non-leaf nodes. case class Dingus(y: Int) extends Innocent ^ three errors found