"hello world" in Scala in 4 ways. http://stackoverflow.com/questions/15182496/why-does-this-code-print-hello-world

HelloWorld.scala

// from http://stackoverflow.com/questions/15182496/why-does-this-code-print-hello-world
import java.util.Random
import scala.annotation.tailrec

object HelloWorld extends App {
  println(randomString(-229985452) +" "+ randomString(-147909649))
  println(randomString2(-229985452) +" "+ randomString2(-147909649))
  println(randomString3(-229985452) +" "+ randomString3(-147909649))
  println(randomString4(-229985452) +" "+ randomString4(-147909649))
  def randomString(i :Int) :String = {
    val rand = new Random(i)
    val sb = new StringBuilder()
    rs(rand.nextInt(27))
    @tailrec
    def rs(k :Int) {
      if (k == 0) return
      else {
        sb.append(('`' + k).toChar)
        rs(rand.nextInt(27))
      }
    }
    sb.toString
  }

  def randomString2(i :Int) :String = {
    val rand = new Random(i)
    def mkList(rand :Random) :List[Int] = {
      val k = rand.nextInt(27)
      if (k == 0) Nil
      else k :: mkList(rand)
    }
    ("" /: mkList(rand)){ (x, y) => x + (('`' + y).toChar.toString) }
  }

  def randomString3(i :Int) :String = {
    val rand = new Random(i)
    @tailrec
    def mkList(l :List[Int]) :List[Int] = {
      val k = rand.nextInt(27)
      if (k == 0) l
      else mkList(k :: l)
    }
    ("" /: mkList(Nil)){ (x, y) => (('`' + y).toChar.toString) + x }
  }

  def randomString4(i :Int) :String = {
    val rand = new Random(i)
    val sb = new StringBuilder()
    Iterator.continually(rand.nextInt(27)).takeWhile(_ != 0).foreach(k => sb.append(('`' + k).toChar.toString))
    sb.toString
  }
}