viewtest.scala:43 error: type mismatch;
 found   : scala.List[<type a in method compareTo>]
 required: scala.List[<type a in method view3>]
        case y1: List[a] => compareLists(x, y1)
                                            ^
viewtest.scala:104 error: ambiguous implicit value:
 both method view4 in object O of type [a](a)a
 and method identity in object Predef of type [a](a)a
 match expected type (test.Str) => test.Ordered[test.Str]
        t = t insert Str(s)
              ^
two errors found