def message(formatter: Formatter): String = {
      import formatter._
      s"""${line(kind, source.name)} // THIS LINE SEEMS TO APPEAR EVERYWHERE
         |>> Cannot derive ${magenta(classSym.name)} for empty enum '${red(sym.name)}'.
         |
         |${code(loc, "illegal derivation")}
         |
         |Flix cannot derive any trait instances for empty enumerations.
         |""".stripMargin
    }