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post.scala

sealed trait PVError extends Product with Serializable

object PVError {
  case object NoIp             extends PVError
  case object AlreadyTracked   extends PVError
  case object PageNotFound     extends PVError
  case object InvalidTimestamp extends PVError

  //helper functions to upcast easily
  val noIp: PVError             = NoIp
  val alreadyTracked: PVError   = AlreadyTracked
  val pageNotFound: PVError     = PageNotFound
  val invalidTimestamp: PVError = InvalidTimestamp
}