package com; import scala.xml._ object Main { def main(args : Array[String]) : Unit = { var m : PartialFunction[Any, Any] = { case SafeNodeSeq(s @ _*) => println(s) } println(m( ++ )) println(m.isDefinedAt( ++ )) } } object SafeNodeSeq { def unapplySeq(any: Any) : Option[Seq[Node]] = any match { case s: Seq[_] => Some(s flatMap ( _ match { case n: Node => n case _ => NodeSeq.Empty })) case _ => None } }