function parse($file)
 {
     // Attempt to use proper XML parsers first
     if (extension_loaded('simplexml')) {
         $parser = new WXR_Parser_SimpleXML();
         $result = $parser->parse($file);
         // If SimpleXML succeeds or this is an invalid WXR file then return the results
         return $result;
     } else {
         if (extension_loaded('xml')) {
             $parser = new WXR_Parser_XML();
             $result = $parser->parse($file);
             // If XMLParser succeeds or this is an invalid WXR file then return the results
             return $result;
         }
     }
     // use regular expressions if nothing else available or this is bad XML
     $parser = new WXR_Parser_Regex();
     return $parser->parse($file);
 }

 function parse($file)
 {
     // Attempt to use proper XML parsers first
     if (extension_loaded('simplexml')) {
         $parser = new WXR_Parser_SimpleXML();
         $result = $parser->parse($file);
         // If SimpleXML succeeds or this is an invalid WXR file then return the results
         if (!is_wp_error($result) || 'SimpleXML_parse_error' != $result->get_error_code()) {
             return $result;
         }
     } else {
         if (extension_loaded('xml')) {
             $parser = new WXR_Parser_XML();
             $result = $parser->parse($file);
             // If XMLParser succeeds or this is an invalid WXR file then return the results
             if (!is_wp_error($result) || 'XML_parse_error' != $result->get_error_code()) {
                 return $result;
             }
         }
     }
     // We have a malformed XML file, so display the error and fallthrough to regex
     if (isset($result) && defined('IMPORT_DEBUG') && IMPORT_DEBUG) {
         echo '<pre>';
         if ('SimpleXML_parse_error' == $result->get_error_code()) {
             foreach ($result->get_error_data() as $error) {
                 echo $error->line . ':' . $error->column . ' ' . esc_html($error->message) . "\n";
             }
         } else {
             if ('XML_parse_error' == $result->get_error_code()) {
                 $error = $result->get_error_data();
                 echo $error[0] . ':' . $error[1] . ' ' . esc_html($error[2]);
             }
         }
         echo '</pre>';
         echo '<p><strong>' . __('There was an error when reading this WXR file', 'wordpress-importer') . '</strong><br />';
         echo __('Details are shown above. The importer will now try again with a different parser...', 'wordpress-importer') . '</p>';
     }
     // use regular expressions if nothing else available or this is bad XML
     $parser = new WXR_Parser_Regex();
     return $parser->parse($file);
 }