Url.scala

case class Url(
  _host: String,
  _path: Seq[String] = Seq.empty[String],
  _query: Map[String, List[String]] = Map.empty[String, List[String]].withDefaultValue(Nil),
  _fragment: Option[String] = None,
  _scheme: Option[String] = None,
  _port: Option[Int] = None) {
  def host(host: String) = copy(_host = host)
  def param(k: String, v: String) = copy(_query = _query + (k -> (v :: _query(k))))
  def path(p: String) = copy(_path = p.split("/").filter(_.nonEmpty).toList)
  def fragment(f: String) = copy(_fragment = Some(f))
  def port(p: Int) = copy(_port = Some(p))
  def scheme(s: String) = copy(_scheme = Some(s))
}