gistfile1.xml

<mxml:xquery-transformer>
  <mxml:xquery-text>
    <![CDATA[
      xquery version "3.0";
      declare variable $document external;
      let $animal := "Duck"
      return
        switch ($animal)
          case "Cow" return <Moo />
          case "Cat" return <Meow/>
          case "Duck" return <Quack />
          case "Dog" case "Pitbull" return <Wuff/>
          default return "What's that odd noise?"
    ]]>
  </mxml:xquery-text>
</mxml:xquery-transformer>