如何准备(play框架，scala)Json写入对象列表的选项，例如
case class Person(name: String, age: Int, relations: Option[List[Person]])
我尝试了以下写入
implicit val personWrites: Writes[Person] = (
(__ \ "name").write[String] and
(__ \ "age").write[Int] and
(__ \ "relations").lazyWrite[Option[Writes.traversableWrites[Person](personWrites)]])(unlift(Person.unapply))
它不起作用，有人可以帮助我以正确的方式创建这些 Json 写入
最佳答案
你已经很接近了:
implicit val personWrites: Writes[Person] = (
(__ \ "name").write[String] and
(__ \ "age").write[Int] and
(__ \ "relations").lazyWriteNullable(Writes.traversableWrites(personWrites)))(unlift(Person.unapply))
关于json - 在递归选项列表上进行惰性写入，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20168135/