printInfo.scala

trait SentientBeing
trait Animal extends SentientBeing
case class Dog(name: String) extends Animal
case class Person(name: String, age: Int) extends SentientBeing
case class Lion(name: String) extends Animal

def printInfo(x: SentientBeing) = x match {
  case Person(name, age) => name + " is " + age + " years old."
  case Dog(name) => "the name is " + name
  case _ => "I am not sure"
}

println(printInfo(new Person("She", 15)))
println(printInfo(new Dog("Tama")))
println(printInfo(new Lion("Lion")))