note 91159 added to language.exceptions

If you intend on creating a lot of custom exceptions, you may find this code useful. I've created an interface and an abstract exception class that ensures that all parts of the built-in Exception class are preserved in child classes. It also properly pushes all information back to the parent constructor ensuring that nothing is lost. This allows you to quickly create new exceptions on the fly. It also overrides the default __toString method with a more thorough one. <?php interface IException { /* Protected methods inherited from Exception class */ public function getMessage(); // Exception message public function getCode(); // User-defined Exception code public function getFile(); // Source filename public function getLine(); // Source line public function getTrace(); // An array of the backtrace() public function getTraceAsString(); // Formated string of trace /* Overrideable methods inherited from Exception class */ public function __toString(); // formated string for display public function __construct($message = null, $code = 0); } abstract class CustomException extends Exception implements IException { protected $message = 'Unknown exception'; // Exception message private $string; // Unknown protected $code = 0; // User-defined exception code protected $file; // Source filename of exception protected $line; // Source line of exception private $trace; // Unknown public function __construct($message = null, $code = 0) { if (!$message) { throw new $this('Unknown '. get_class($this)); } parent::__construct($message, $code); } public function __toString() { return get_class($this) . " '{$this->message}' in {$this->file}({$this->line})\n" . "{$this->getTraceAsString()}"; } } ?> Now you can create new exceptions in one line: <?php class TestException extends CustomException {} ?> Here's a test that shows that all information is properly preserved throughout the backtrace. <?php function exceptionTest() { try { throw new TestException(); } catch (TestException $e) { echo "Caught TestException ('{$e->getMessage()}')\n{$e}\n"; } catch (Exception $e) { echo "Caught Exception ('{$e->getMessage()}')\n{$e}\n"; } } echo '<pre>' . exceptionTest() . '</pre>'; ?> Here's a sample output: Caught TestException ('Unknown TestException') TestException 'Unknown TestException' in C:\xampp\htdocs\CustomException\CustomException.php(31) #0 C:\xampp\htdocs\CustomException\ExceptionTest.php(19): CustomException->__construct() #1 C:\xampp\htdocs\CustomException\ExceptionTest.php(43): exceptionTest() #2 {main} ---- Server IP: 64.71.164.2 Probable Submitter: 24.131.71.109 ---- Manual Page -- http://www.php.net/manual/en/language.exceptions.php Edit -- https://master.php.net/note/edit/91159 Del: integrated -- https://master.php.net/note/delete/91159/integrated Del: useless -- https://master.php.net/note/delete/91159/useless Del: bad code -- https://master.php.net/note/delete/91159/bad+code Del: spam -- https://master.php.net/note/delete/91159/spam Del: non-english -- https://master.php.net/note/delete/91159/non-english Del: in docs -- https://master.php.net/note/delete/91159/in+docs Del: other reasons-- https://master.php.net/note/delete/91159 Reject -- https://master.php.net/note/reject/91159 Search -- https://master.php.net/manage/user-notes.php