如何在Scala中为枚举添加方法？

object Unit extends Enumeration {  abstract class UnitValue(var name: String) extends Val(name) {    def m: Unit  }  val G = new UnitValue("g") {    def m {        println("M from G")    }  }  val KG = new UnitValue("kg") {    def m {        println("M from KG")    }  }}