import scala.util.regexp.WordExp; import scala.util.automata.WordBerrySethi; object BoolWordExp extends WordExp { type _labelT = MyLabels; type _regexpT = RegExp; abstract class MyLabels extends Label ; case class MyLabel(c:Char) extends MyLabels; } object MyTranslator extends WordBerrySethi { override val lang = BoolWordExp; import lang._; override protected def seenLabel( r:RegExp, i:Int, label: _labelT ): Unit = { super.seenLabel(r,i,label) } }