binding trait instance

ResId.scala

trait ResId {
  def toASCIIString: String
}
object ResId {
  def apply(uri: String): ResId = new StringUri(uri)
  def apply(uri: URI): ResId = new StringUri(uri.toString)

  private def validated(uri: String): String = URI.create(uri).toString
  case class StringUri(value: String) extends ResId {
    override val toASCIIString: String = validated(value)
  }
}

def convert(resId: ResId): Rdf#URI = URI(resId.toASCIIString)

implicit val resIdBinder: PGBinder[Rdf, ResId] = new PGBinder[Rdf, ResId] {
  override def toPG(t: ResId): PointedGraph[Rdf] = convert(t).toPG
  override def fromPG(pointed: PointedGraph[Rdf]): Try[ResId] = pointed.pointer.fold (
    uri => Success(ResId(uri.getString)),
    _ => Failure(new IllegalArgumentException),
    _ => Failure(new IllegalArgumentException)
  )
}