anchor.diff:  passage
       :   {ParseMode == EVineParseMode.EXPR}? evalExprMode NL? EOF // active only if we're expr parse mode
       |   block* NL? EOF
  -    |   { NotifyErrorListeners(reserved_char); } RESERVED_CHARS 
  +    |   { NotifyErrorListeners(errReservedChar); } RESERVED_CHARS 
       //|   { NotifyErrorListeners("Error char"); } ERROR_CHAR
       ;
   
  
positive.code: 
  stringLiteral
      :   STRING
      |   { NotifyErrorListeners(reserved_char); } ILLEGAL_STRING
      ;
  
  // Variable access. The '$' prefix is optional
  
negative.code:     // by default, parse as a passage (full mode)
      public EVineParseMode ParseMode = EVineParseMode.FULL;
  
      private static readonly string errReservedChar =
          "'\u000B' (vertical tabulation) is a reserved character and is not allowed to be used!";
      
      private static readonly string errVarDefReservedKw =
  