in scala-repl/src/main/scala/spark/ztools.sc [351:362]
override def accept(obj: Any): Boolean =
obj match {
case _: Byte => true
case _: Short => true
case _: Boolean => true
case _: Char => true
case _: Int => true
case _: Long => true
case _: Float => true
case _: Double => true
case _ => false
}