trait Component { }
trait TransformComponent extends Component {
    var x : Int = 0;
}
trait VelocityComponent extends TransformComponent {
    var vx : Int = 0;
}
trait RenderComponent extends TransformComponent with VelocityComponent {
    def render() = System.out.println("x=" + x);
}
class Entity { }
 
object Foo {
    def updatePhysical(body:VelocityComponent) {
        body.x += body.vx;
    }
}
 
object Main extends App {
  val player = new Entity with TransformComponent with RenderComponent;
  player.vx = 10;
  Foo.updatePhysical(player);
  player.render();
}

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