$error = new Phpfox_Error(); $error->addError('Field is required'); if (!$error->isPassed()) { echo $error; }This code creates a new instance of the Phpfox_Error class, adds an error message to it, and then checks if the error message is empty using isPassed(). If it's not empty, the error message is printed out. The package library for Phpfox_Error is Phpfox Core.