How can I get XStream to output Scala lists nicely? Can I write a custom converter?

Question

This code:

println(new XStream.toXML(List(1,2,3)))

produces this XML:

  &         


        

Answer 1

There is only one instance of an empty list, which is the object Nil.

Answer 2

Not seconds after posting the question, the answer came to me, here is a working implementation of unmarshal:

  def unmarshal( reader: HierarchicalStreamReader, context: UnmarshallingContext ) = {
    var list : List[_] = Nil 
    while (reader.hasMoreChildren()) {
      reader.moveDown();
      val item = readItem(reader, context, list);
      list = list ::: List(item) // be sure to build the list in the same order
      reader.moveUp();
    }
    list
  }