The epic fight between inheritance and type systems, in pseudo-Scala

inheritance_vs_types.scala

class StrangeIntQue extends Queue[Int] {
  override def append(x: Int) {
    println(Math.sqrt(x))
    super.append(x)
  }
}

val x: Queue[Any] = new StrangeIntQueue
x.append("abc") // Math.sqrt("abc") ?