Returning XML content

XML content is introduced by '<'

function test (map $m) as xml return
<rdf:RDF xmlns:rdf="http://www.w3c.org/RDF/"
         xmlns:lit="http://www.isotopicmaps.org/tmql/use-cases/literature/">{
  forall [ $d (tutorial)
           bn: $title
           oc (download): $url ] in $m
  return
     <lit:tutorial rdf:about="{$url}">
        <lit:title>{$title}</lit:title>{
        forall [ (is-author-of)
                 author : $a
                 opus   : $d ]
        return
        <lit:author>{$a/bn}</lit:author>
        }
}<rdf:RDF>

query follows the structure of the XML document, heritage from XQuery, of course

evaluation context within XML is string

idea (not implemented): if variable is structural (association, characteristics) then stringification could return XTM code