object Foo extends Properties("Foo") {
  import Gen._

  property("bar") =
    forAll(listOfN(4, choose(0, 255))) { n =>
      println(n)
      false
    }
}

// --- OUTPUT ---
// List(19, 152, 240, 72)
// List(19, 152)
// List(19)
// List()
// [info] ! Foo.bar: Exception raised on property evaluation.
// [info] > ARG_0: List()
// [info] > ARG_0_ORIGINAL: List("19", "152", "240", "72")
// [info] > Exception: scala.MatchError: List() (of class scala.collection.immutable.Nil$)
// [info] ScalaTest