import scala.reflect.runtime.universe._

object Test {
  object Bippy {
    def unapply(x: Apply with Select) = Some(x.qualifier)
  }
  def main(args: Array[String]): Unit = {
    val x = Apply(EmptyTree, Nil)
    // Direct invocation correctly disallowed
    // Bippy.unapply(x)
    //
    // Pattern matcher allows, unsoundly
    x match { case Bippy(_) => () }
  }
}
// and...
//
// java.lang.ClassCastException: scala.reflect.internal.Trees$Apply cannot be cast to scala.reflect.api.Trees$SelectApi
//   at Test$Bippy$.unapply(a.scala:5)
//   at Test$.main(a.scala:13)
//   at Test.main(a.scala)