json - 自动推导结构类型的编解码器

Question

给定以下 JSON 结构

  val rawJson =
    """
      |{
      |  "users": [
      |    {
      |      "name": "Mario",
      |      "age": 10,
      |      "address": {
      |        "street": "13 Blvd",
      |        "postcode": "ABC 123"
      |      }
      |    },
      |    {
      |      "name": "Wario",
      |      "age": 70,
      |      "address": {
      |        "street": "22 Blvd",
      |        "postcode": "CBA 321"
      |      }
      |    }
      |  ]
      |}
    """.stripMargin

和对应的型号

  case class Address(street: String, postcode: String)
  case class User(name: String, age: Int, address: Address)
  case class RequestBody(users: List[User])

circe 能够自动反序列化

decode[RequestBody](rawJson))

当模型通过结构类型定义时是否可以自动反序列化

  case class RequestBody(users: List[ {
    val name: String
    val age: Int
    val address: {
      val street: String
      val postcode: String
    }
  }])

Answer 1

我觉得不是。Circe 在底层使用 Shapeless 来生成编解码器。而Shapeless 适用于ADT ，即密封特征+案例类。结构类型不是 ADT。