docs: function(err) {
          // console.log('errorHandler', url, err);
          window.clearTimeout(timeout);
  
          var message = err;
  
          if (request && request.tagName && request.error) {
              var ERROR_STATE = ['', 'ABORTED', 'NETWORK', 'DECODE', 'SRC_NOT_SUPPORTED'];
              message = 'MediaError: ' + ERROR_STATE[request.error.code] + ' ' + request.src;
          } else if (request && request.statusText) {
              message = request.statusText;
          } else if (err && err.message) {
              message = err.message;
          } else if (err && err.type) {
              message = err.type;
          }
  
          loader.emit('error', 'Error loading "' + basePath + url + '" ' + message);
  
          destroy();
      }