anchor.diff:      ;
   
   subSelect
  -    : ^(SUBSELECT whereClause* solutionModifier)
  +    : ^(SUBSELECT whereClause* datasetClause* solutionModifier)
       ;
       	
   selectClause
  
positive.code:     | ^(IRI expression)
      | ^(URI expression)
      | ^(BNODE expression)
      | RAND
      | ^(ABS expression)
      | ^(CEIL expression)
  
negative.code:     ;
      
  iriRefOrFunction
      : ^(FUNCTION f=iriRef ^(ARG_LIST (a=argList)))
      | ^(FUNCTION f=iriRef)
      ;
  
  rdfLiteral
  