/**
* Add this logger to the chain.
* Existing loggers remain in the list. Use {@link set_logger()} to replace
* the whole chain of current loggers.
* @param LOGGER $logger
* @param boolean $copy_settings Copies settings from the current logger if
* <code>True</code>.
*/
public function add_logger($logger, $copy_settings = true)
{
if (isset($this->logger)) {
$this->logger->add_logger($logger, $copy_settings);
} else {
$this->set_logger($logger, $copy_settings);
}
}
