gistfile1.txt

scala> class S[A]( val theSeq:Seq[A] ) extends Seq[A]{
     |   def apply(n:Int ) = theSeq(n)
     |   def length = theSeq.length
     |   override def iterator = theSeq.iterator
     |   override def toString = "hogehoge"
     | }
defined class S

scala> new S( List("foo","bar"))
res15: S[java.lang.String] = line35(foo, bar)

scala> res15.toString
res16: java.lang.String = hogehoge