More Partial Functions

Here I am defining a couple of PartialFunctions and using them:

  def main(args :Array[String]) :Unit = {

    def f1 : PartialFunction[List[String], String] = {
      case "a" :: rest => "I got an A"
    }
    def f2 : PartialFunction[List[String], String] = {
      case "a" :: "b" :: rest => "I got an A and the next letter is a B"
    }
    def f3 = f2 orElse f1

    println( handleRequest2( "a"::"c"::"a"::"b"::Nil)(f3) )
  }

  def handleRequest2(req : List[String])
      (exceptions : PartialFunction[List[String], String]) : String = {
    if (req.isEmpty) {
      ""
    } else if (exceptions.isDefinedAt(req)) {
      exceptions(req) + "\n" + handleRequest2( req.tail )(exceptions)
    } else {
      "Normal handle "+req.head+" ..done" + "\n" + handleRequest2( req.tail(exceptions)
    }
  }

Output [is unsurprisingly]:

I got an A
Normal handle c ..done
I got an A and the next letter is a B
Normal handle b ..done