anchor.diff:      ;   
       
   load 	  
  -    : LOAD SILENT? iriRef (INTO graphRef)?
  +    : LOAD SILENT? iri (INTO graphRef)?
       ;
       
   clear
  
positive.code:     ;
  
  datasetClause
      : FROM NAMED? iriRef
      ;
  
  whereClause
  
negative.code:     ;
  
  graphPatternNotTriples
      : groupOrUnionGraphPattern | optionalGraphPattern | minusGraphPattern | graphGraphPattern | serviceGraphPattern | filter | bind | inlineData
      ;
  
  optionalGraphPattern
  