title: Derived Scala case class with same member variables as base
body: <p>Is there a nicer way of doing this?</p>
  
  <pre><code>scala&gt; case class A(x : Int)
  defined class A
  
  scala&gt; case class B(override val x : Int, y : Int) extends A(x)
  defined class B
  </code></pre>
  
  <p>I'm extending A with B and adding an extra member variable. It would be nice not to have to write <code>override val</code> before the x.</p>