我怎麼能寫一個使用繼承

Question

作爲例子寫很多類在遊戲框架我有類

trait Advert 

case class Car(brand: String) extends Advert 
case class House(price: Long) extends Advert 

object AdvertCompanion[T <: Advert] 
object Car extends AdvertComnation[Car] 
object House extends AdvertComnation[House] 

我不想寫Json.writes [..]如果類的每一個同伴。我想寫在對象AdvertCompanion中。但後來我這樣做，我得到錯誤No unapply function found

Answer 1

也許這將有益

Play Framework/Scala Json Generics