Call List (simplified with ! operator)

declare default element namespace "http://www.tei-c.org/ns/1.0";
 
(: 
  Which actors appear in each scene?
  - group by scenes
  - show unique actors in each scene 
:)

for $act in //div1[@type='act']
for $act-number in $act/@n
for $scene in $act//div2[@type='scene']
for $scene-number in $scene/@n
for $whoville in $scene//*[@who]
for $person in $whoville/@who ! tokenize(., "(#)|( #)")
group by $act-number, $scene-number
order by $act-number, $scene-number
return
  <scene act="{$act-number}" scene="{$scene-number}">
   {
     for $p in $person
     group by $p
     order by $p
     return $p
   }
  </scene>

Query from http://xqueryinstitute.org/ workshop, June 2014. Input is Folger's edition of Julius Caesar.