code: func newScanModelRefHandler(fieldNames []string, mr *modelRef) ReplyHandler {
  	return func(reply interface{}) error {
  		fieldValues, err := redis.Values(reply, nil)
  		if err != nil {
  			if err == redis.ErrNil {
  				return newModelNotFoundError(mr)
  			}
  			return err
  		}
  		if err := scanModel(fieldNames, fieldValues, mr); err != nil {
  			return err
  		}
  		return nil
  	}
  }
docs: // newScanModelRefHandler works exactly like the exported NewScanModelHandler,
  // but it expects a *modelRef as the final argument instead of a Model. See
  // the documentation for NewScanModelHandler for more information.