anchor.diff:      ;
   
   datasetClause
  -    : FROM NAMED? iriRef
  +    : FROM NAMED? iri
       ;
   
   whereClause
  
positive.code: triplesSameSubject
      : varOrTerm propertyListNotEmpty | triplesNode propertyList 
      ;
  
  propertyListNotEmpty
      : verb objectList (SEMICOLON (verb objectList)?)* 
      ;
      
  propertyList
      : propertyListNotEmpty?
      ;
  
  objectList
      : object (COMMA object)*
  
negative.code:     ;   
      
  load 	  
      : LOAD SILENT? iri (INTO graphRef)?
      ;
      
  clear
  