anchor.diff:     ;
   
   PREFIXED_NAME
  -  : PNAME_LN | PNAME_NS
  -  ;
  -
  -// extends PREFIXED_NAME to allow right-hand side curly brackets and slash, and force one right-hand side opening curly bracket
  +   : PNAME_NS PN_LOCAL
  +  ;
  +
  +// extends PREFIXED_NAME to allow right-hand side curly brackets, and force one right-hand side opening curly bracket
   PREFIXED_NAME_EXT
     : PNAME_NS PN_LOCAL_EXT
     ;
  -
  -PNAME_LN
  -   : PNAME_NS PN_LOCAL
  -   ;
   
   BLANK_NODE_LABEL
     : '_:' (PN_CHARS_U | [0-9]) ((PN_CHARS | '.')* PN_CHARS )?
  
positive.code:   : '{' RIGHT_PART_TAIL_EXT ? | RIGHT_PART_FIRST_CHAR RIGHT_PART_TAIL_EXT_MAND
    ;
  
  // extends PN_LOCAL in the original grammar to allow slash
  PN_LOCAL
    : RIGHT_PART_FIRST_CHAR RIGHT_PART_TAIL?
    ;
  
negative.code:   ;
  
  fragment IRIREF_INNER_CHAR_EXT
    :  (IRIREF_INNER_CHAR | '{' | '}')
    ;
  
  fragment VARIABLE_CHAR
  