gistfile1.scala

trait Writes[T] {
  def writes(o: T): JsValue
}

trait Reads[T] {
  def reads(json: JsValue): T
}

trait Format[T] extends Writes[T] with Reads[T]

object JsonSerialization {
  def tojson[T](o: T)(implicit tjs: Writes[T]): JsValue = tjs.writes(o)

  def fromjson[T](json: JsValue)(implicit fjs: Reads[T]): T = fjs.reads(json)
}