Parse a time string #scala

gistfile1.scala

val timeParser: (String => (String, String)) = { str =>
  val ptn = """^(0?[0-9]|1[0-9]|2[0-3]):(0?[0-9]|[1-5][0-9])$""".r
  ptn findFirstIn str match {
    case Some(ptn(h, m)) => ("%02d".format(h.toInt), "%02d".format(m.toInt))
    case None => ("--", "--")
  }
}

Array("01:23", "1:23", "12:34", "23:60", "25:00") foreach { str =>
  val (hour, min) = timeParser(str)
  println("%s:%s".format(hour, min))
}