The Nothing Type in Scala PRO

The main usage for Nothing is when specifying the return type for methods which never return normally (e.g. throw an exception when been called).

object Sample
{
  def main(args:Array[String]):Unit =
  {
    val ob = getMyStack[Int](10)
  }
  def getMyStack[T](num:Int) =
  {
    new EmptyMyStack[T]
  }
}

abstract class MyStack[T](size:Int)
{
  def data:T;
}

class EmptyMyStack[T] extends MyStack[T](0)
{
  def data:Nothing = throw new Exception("empty stack");
}

The following video clip overviews this code sample, shows its execution and explains one of the main common cases in which we will use the Nothing type.