ifalok007

val twentySomethings = for (user <- userBase if user.age >=20 && user.age < 30) yield user.name // i.e. add this to a list
twentySomethings.foreach(println)

ifalok007

trait Greeter {
  def meet(name: String): Unit
  def greet(name: String): Unit = println("Hello, " + name + "!")
}

ifalok007

object IdFactory {
  private var counter = 0
  def create(): Int = {
    counter += 1
    counter
  }
}
val newId: Int = IdFactory.create()// YOU ACCESS OBJECTS BY ITS NAME