sealed trait CL3Literal case object IntLit extends CL3Literal case object CharLit extends CL3Literal case object BooleanLit extends CL3Literal case object UnitLit extends CL3Literal sealed trait Tree case class LetL(value: CL3Literal) extends Tree case object LetP extends Tree case object LetC extends Tree case object LetF extends Tree object Test { def transform(tree: Tree) : Any = tree match { case LetL(CharLit) => ??? } }