在Scala中,我可以覆盖包含列表的具体字段并在子类中附加一些内容

trait RequiredThings {
  val requiredThings: Seq[String]
}

class SimpleCalculator with RequiredThings {
  val requiredThings = List("a","b")
}

class ComplicatedCalculator extends SimpleCalculator with RequiredThings {
  self: SimpleCalculator =>
  override val requiredThings:List[String] = List("c") ::: self.requiredThings
}

在这个版本中,我使用的是自我类型的注释,但我不是完全肯定的,这是要走的路.我想我可以通过将requiredThings转换为一个方法来实现它,但我想把它作为一个字段来尝试.

最终解决方案

trait RequiredThings {
  def requiredThings: Seq[String]
}

class SimpleCalculator with RequiredThings {
  def requiredThings = List("a","b")
}

class ComplicatedCalculator extends SimpleCalculator with RequiredThings {
  override def requiredThings:List[String] = List("c") ::: super.requiredThings
}