recipe count_heads (&$count : NNInt, $search : Text,
             $people ::= $fed.data.db1.people) {
         with value-filter filt 
           (Bool <-- $topic : Tuple, $search : Text) {
             $.name like ('%' ~ $search ~ '%')
         }
         $count := r# ($people where <nlx.lib.filt>( $>search ))
     }