object Test { def confirmSame(x: Any) = assert(x.## == x.hashCode, "%s.## != %s.hashCode".format(x, x)) def confirmDifferent(x: Any) = assert(x.## != x.hashCode, "%s.## == %s.hashCode (but should not)".format(x, x)) def main(args: Array[String]): Unit = { /** Just a little sanity check, not to be confused with a unit test. */ List(5, 5.5f, "abc", new AnyRef, ()) foreach confirmSame List(5.0f, 1.0d, -(5.0f), (-1.0d)) foreach confirmDifferent } }