gistfile1.java

/*
 * Recursive xml transformation util. Provides a simplistic tool for
 * registering transforms as functions, which will be called recursively
 * on each node of the tree.
 */
import scala.xml._

trait XmlRenderer {
  
  val handlers: Map[(Node) => Boolean, (Node) => Node]
  
  def render(seq: NodeSeq): NodeSeq = seq.map(n =>
    n match {
      case e: Elem => processNode(e) match {
        case Some(handled)  => handled
        case None           => Elem(e.prefix, e.label, e.attributes, e.scope, render(e.child):_*)
      }
      case _ => n
    }
  )
  
  def processNode(n: Node): Option[Node] =
    handlers.filterKeys(_(n)).values.find((v_) => true).map(_(n))
}

object Loader extends XmlRenderer {
  val handlers = Map(
    ((n: Node) => n.label == "span") -> ((n: Node) =>
      Text("TRANSFORMED"))
  )
}