class MyBook<T>(var bookText:T)
{
     fun Show()
     {
          println(bookText.toString())
     }
}

fun main() {
     val book1 = MyBook("Hello!")
     book1.Show()

     val book2 = MyBook(123)
     book2.Show()
}

interface MyContent
{
     fun Display();
}

class MyBook<T>(var text:T) where T:MyContent
{
}

fun main() {
     val book1 = MyBook(object : MyContent
          {
               override fun Display () { println("Hello Good!") }
          }
     )
     book1.text.Display()
}