使用多重继承从scala中的不同特征调用不同的方法

trait Drawable {
  def draw
  def paint
}

trait Cowboy extends Drawable {
  override def draw() { println("Bang!") }
  override def paint(){ println("I need this to be painted")}
}

trait Artist extends Drawable {
  override def draw() { println("A pretty painting") }
  override def paint(){ println("I don't want this to be painted")}
}

class CowboyArtist extends Cowboy with Artist

object Main extends App {
  (new CowboyArtist()).draw() // A pretty painting
  (new CowboyArtist()).paint() // I don't want this to be painted
}

在这里,Artist和Cowboy继承了Drawable并覆盖了draw和paint方法. CowboyArtist以同样的顺序继承了Cowboy和Artist.根据我的read,scala根据其继承的顺序和最右边特征的方法执行来确定要调用的方法.

但是,如果我想要从一个特征中调用其中一个方法,另一个方法来自另一个特征,如你所见,我希望从Artist特征执行draw方法,但我希望从牛仔的特质.

这可能吗？如果不是什么是解决方法？

class CowboyArtist extends Cowboy with Artist {
    override def paint = super[Cowboy].paint
}

super [Trait]允许您从要调用的线性化中选择确切的特征.

所以现在：

scala> (new CowboyArtist()).paint()
I need this to be painted

scala> (new CowboyArtist()).draw()
A pretty painting

附：你也可以在内部特征中使用super [Trait],这样你就可以在将它混合到类之前创建一个具有正确优先级的mixin：

trait CowboyArtistMixin extends Cowboy with Artist{
    override def paint = super[Cowboy].paint
}

class CowboyArtist extends CowboyArtistMixin