Scala视图界定

  @Test
  def testOK() = {
    case class Student[T, S <% Comparable[S]](var name: T, var height: S)
    val s = Student("john", "170")
    //下面这条语句在视图界定中是合法的
    //因为Int类型此时会隐工转换为
    //RichInt类，而RichInt类属于Comparable、
    //继承层次结构
    val s2 = Student(190, 170)

  }