anchor.diff:      rule dot_field_item:
           [ VAR COLON ] dot_item
   
  -    rule tagged_match_arg:
  -        VAR COLON DOT VAR
  -
       rule dot_field_list:
           dot_item
           | NUM
           | VAR
           | LBRACE dot_field_item (COMMA dot_field_item)* RBRACE
   
  -    rule dot_field_ltagged:
  +    rule tagged_dot_list:
           TOKTAGGED VAR
           [
               (dot_field_list
               | LPAREN
                   ( dot_field_list
  -                | dot_field_ltagged
  +                | tagged_dot_list
                   )
                   RPAREN
               )
           ]
   
       rule dot_field_selection:
  -        dot_field_ltagged
  -        | LPAREN dot_field_ltagged RPAREN
  +          tagged_dot_list
  +        | LPAREN tagged_dot_list RPAREN
           | NUM
   
       # A factor is the product and division of terms
  
positive.code:             [ provisos_clause ] SEMICOLON
              (   method_declaration
              |   TOKPARAMETER VAR  EQUAL expr<<[]>> SEMICOLON
              |   TOKDEFAULT_CLOCK [ VAR ]
                    [ LPAREN VAR [ COMMA VAR ] RPAREN ] [ EQUAL expr<<[]>> ] SEMICOLON
              |   TOKINPUT_CLOCK [VAR] [ LPAREN VAR [ COMMA VAR ] RPAREN ]
                    EQUAL expr<<[]>> SEMICOLON
              |   TOKOUTPUT_CLOCK VAR LPAREN VAR [ COMMA VAR ] RPAREN SEMICOLON
              |   TOKNO_RESET SEMICOLON
              |   TOKSCHEDULE import_arg
                    ( TOKCF | TOKSB | TOKSBR | TOKC ) import_arg SEMICOLON
              |   TOKDEFAULT_RESET VAR  LPAREN [ VAR ] RPAREN  [ EQUAL expr<<[]>>] SEMICOLON
              |   TOKINPUT_RESET [ VAR ]  LPAREN [ VAR ] RPAREN
                    [ TOKCLOCKED_BY LPAREN VAR RPAREN ]
                    EQUAL expr<<[]>> SEMICOLON
              |   TOKOUTPUT_RESET VAR  LPAREN VAR RPAREN
                    TOKCLOCKED_BY LPAREN VAR RPAREN SEMICOLON
              )*
              TOKENDMODULE [ COLON  VAR ]
          )
  
negative.code:         TOKENDACTIONVALUE
  
      rule case_statement:
          TOKCASE paren_expression
          ( TOKMATCHES
            (
                ( dot_field_selection
                | LBRACE tagged_dot_list (COMMA tagged_dot_list)* RBRACE
                | TOKDEFAULT
                | VAR 
                )
  