Support of sum types for Scala wanted

[plokhotnyuk]

They have an abstract class or a trait as a base (usually sealed) and several sub-classes or implementations (usually case classes or objects):

sealed trait ADTBase extends Product with Serializable

case class X(a: Int) extends ADTBase

case class Y(b: String, c: Double) extends ADTBase

case object Z extends ADTBase

Most common representation for them is using of additional field with a discriminator value that usually contains a simple name of sub-class or implementation:

{"type":"Y","b":"VVV","c":777}

[zapov]

In Java this is only supported through the annotation processor.
I'd rather improve the Scala side of things for code-gen than add more options to reflection based implementation ;(