public static function preProcessing(Compiler $compiler, array $params, $prepend, $append, $type)
 {
     $params = $compiler->getCompiledParams($params);
     switch (strtolower(trim((string) $params['enabled'], '"\''))) {
         case 'on':
         case 'true':
         case 'enabled':
         case 'enable':
         case '1':
             $enable = true;
             break;
         case 'off':
         case 'false':
         case 'disabled':
         case 'disable':
         case '0':
             $enable = false;
             break;
         default:
             throw new CompilationException($compiler, 'Auto_Escape : Invalid parameter (' . $params['enabled'] . '), valid parameters are "enable"/true or "disable"/false');
     }
     self::$stack[] = $compiler->getAutoEscape();
     $compiler->setAutoEscape($enable);
     return '';
 }