code: public static function addMarkerComment($content, $caller)
      {
          $lastParsedFile = call_user_func(array($caller, 'getLastParsedFile'));
  
          return
              '<?php '.
              constant($caller.'::COMMENT').
              (is_null($lastParsedFile) ? '' : '/*:'.$lastParsedFile.':*/').
              ' ?>'.
              $content;
      }
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