anchor.diff:  	
   triplesNode
       : OPEN_BRACE graphNode+ CLOSE_BRACE -> ^(COLLECTION graphNode+)
  -    | lsb=OPEN_SQUARE_BRACKET propertyListNotEmpty[new CommonTree(new CommonToken(VAR,"[ ]"))] CLOSE_SQUARE_BRACKET -> ^(VAR[$lsb,"[ ]"] propertyListNotEmpty)
  +    | lsb=OPEN_SQUARE_BRACKET propertyListNotEmpty[new CommonTree(new CommonToken(VAR,"[]"))] CLOSE_SQUARE_BRACKET -> ^(VAR[$lsb,"[]"] propertyListNotEmpty)
       ;
   
   graphNode
  
positive.code:     ;
  
  argList
      : ( nil | OPEN_BRACE DISTINCT? expression ( COMMA expression )* CLOSE_BRACE ) -> DISTINCT? nil* expression*
      ;
  
  expressionList
  
negative.code:     ;
  
  unaryExpression
      : op=NEGATION primaryExpression -> ^(UNARY_NOT[$op] /*NEGATION*/ primaryExpression)
      | op=PLUS primaryExpression -> ^(UNARY_PLUS[$op] /*PLUS*/ primaryExpression)
      | op=MINUS primaryExpression -> ^(UNARY_MINUS[$op] /*MINUS*/ primaryExpression)
      | primaryExpression -> ^(UNARY primaryExpression)
      ;
  
  primaryExpression
  