// Define each registry object separately $dbConfig = new JRegistry( ... ); // database connection settings $emailConfig = new JRegistry( ... ); // email settings $appConfig = new JRegistry( ... ); // general app settings // Merge all three configs into a single registry object $mergedConfig = clone $dbConfig; // start with a clone of the db config $mergedConfig->merge($emailConfig); // merge in the email settings $mergedConfig->merge($appConfig); // merge in the general app settings // Use the merged config object to retrieve settings as needed $dbHost = $mergedConfig->get('db_host'); $emailSender = $mergedConfig->get('email_sender'); $appTitle = $mergedConfig->get('app_title');In this example, we start by creating separate JRegistry instances for each config file (or array). We then use the `merge` method to combine these separate instances into a single, comprehensive configuration object. This code snippet most likely uses the Joomla Framework's JRegistry library, which is a common dependency for Joomla applications and extensions. However, it's possible that this code could be using a different JRegistry library (such as one built in-house by a particular development team), so it's difficult to say for certain without more context.