anchor.diff:      token TOKBDPI: '"BDPI"'
       token TOKBVI: '"BVI"'
   
  -    token NUM: " [0-9]+[\\'dhb\\\\.]*[a-fA-F0-9_]*"
  -    token VAR: " `*[a-zA-Z_][a-zA-Z0-9_]*"
  -    token ANYCHAR: " [a-zA-Z0-9_]*"
  -    token STR:   r' "([^\\"]+|\\.)*"'
  +    token NUM: " "
  +    token VAR: " "
  +    token ANYCHAR: " "
  +    token STR:   " "
       token TYPEVAR: " "
  -
  -    token TOKEN_FIRSTNAME: " "
  +    token CLASSVAR: " "
  +
       token BEGIN: "begin"
       token TOKENDACTIONVALUE: "endactionvalue"
       token TOKENDACTION: "endaction"
  
positive.code: 
      rule instance_statement:
          TOKINSTANCE TYPEVAR LPAREN instance_arg ( COMMA instance_arg )* RPAREN
          [ provisos ] SEMICOLON
          ( function_statement
          | module_declaration
          )*
          TOKENDINSTANCE [ COLON VAR ]
  
negative.code:         # datatype might not be present
          Type_nitem [ VAR ] ( EQUAL | LEQ ) assign_value
  
      rule for_variable_assignment:
          term<<[]>> ( EQUAL | LEQ | LARROW ) assign_value
  
      rule for_statement:
          TOKFOR LPAREN
              for_decl_item (COMMA for_decl_item)* SEMICOLON
              assign_value SEMICOLON
              for_variable_assignment ( COMMA for_variable_assignment )* RPAREN
          single_statement
  
      rule while_statement:
          TOKWHILE LPAREN expr<<[]>> RPAREN
          ( action_statement
          | seq_statement
          | group_statement
          | VAR SEMICOLON
          )
  
      rule return_statement:
          TOKRETURN assign_value SEMICOLON
  
      rule group_statement:
          BEGIN
          statement_list
  