VersionDummy.scala

package com.scalaRethinkdb

object VersionDummy {
  sealed abstract class Version
  object V0_3 extends Version
  object V0_4 extends Version

  object Version {
    implicit object instances extends Wire[Version] {
      def toWire(a: Version): Int = a match {
        case V0_3 => 0x5f75e83e
        case V0_4 => 0x400c2d20
        case _ => throw new RethinkDbUnexpectedResponseError("Version not found.")
      }

      def fromWire(a: Int): Version = a match {
        case 0x5f75e83e => V0_3
        case 0x400c2d20 => V0_4
        case _ => throw new RethinkDbUnexpectedResponseError("Version not found.")
      }
    }
  }
}

Wire.scala

package com.scalaRethinkdb

trait Wire[T] {
  def toWire(a: T): Int
  def fromWire(a: Int): T
}