code: public static function defaultTransform($text)
      {
          #
          # Initialize the parser and return the result of its transform method.
          # This will work fine for derived classes too.
          #
          # Take parser class on which this function was called.
          $parser_class = \get_called_class();
  
          # try to take parser from the static parser list
          static $parser_list;
          $parser = &$parser_list[$parser_class];
  
          # create the parser it not already set
          if (!$parser) {
              $parser = new $parser_class;
          }
  
          # Transform text using parser.
          return $parser->transform($text);
      }
docs: ### Simple Function Interface ###