reduce is args is head,s fold

common.scala

object common extends App {
  val a = "s"
  println(s"wo kao $a")

  case class Foo(val name: String, val age: Int, val sex: Symbol)

  val fooList = Foo("Hugh Jass", 25, 'male) ::
    Foo("Biggus Dickus", 43, 'male) ::
    Foo("Incontinentia Buttocks", 37, 'female) ::
    Nil
  println(fooList)
  val stringList = fooList.foldLeft(List[String]()) { (z, f) =>
    val title = f.sex match {
      case 'male => "Mr."
      case 'female => "Ms."
    }
    z :+ s"$title ${f.name}, ${f.age}"
  }
  println(stringList)
  println(stringList(0))
}