traits.scala

// Legacy
abstract class Lannister {
  def payTheirDebts: Boolean
  def trueLannister = payTheirDebts
}

//Father
trait Tywin extends Lannister{
  override def payTheirDebts = true
}

// Son #1
trait Jamie extends Tywin {
  override def payTheirDebts = true
}

// Son #2
trait Tyrion extends Tywin {
  override def payTheirDebts = true
}

// Daughter #1
trait Cersei extends Tywin {
  override def payTheirDebts = false
}

class Joffrey extends Lannister with Jamie with Cersei

class Tommen extends Lannister with Cersei with Jamie

object GameOfThrones extends App{
  val joffrey = new Joffrey
  println(joffrey.trueLannister) // false

  val tommen = new Tommen
  println(tommen.trueLannister) // true
}