From: glideraerobatics at hotmail dot com Operating system: PHP version: 5.3.0alpha2 PHP Bug Type: Feature/Change Request Bug description: readonly attribute for (public) class variables
Description: ------------ Here is a description of this feature in C#: http://blog.paranoidferret.com/index.php/2007/09/12/csharp-tutorial-the-readonly-keyword/ In a nutshell it allows you to create classes with public variables that are readonly and can only be written to / initialized by the contructor of the class itself. This allows the creation of simple objects without having using accessor methods to protect the internal data that was validated and initialized during construction from corruption. Note: bug http://bugs.php.net/bug.php?id=39467 is about a similar problem but the proposed solution is not quite right. Reproduce code: --------------- class Person { public readonly $name = null; public readonly $age = null; public readonly $weight = null; public function __construct($name, $age, $weight) { { if (!isAgeToWeightRatioSane($age, $weight)) { throw new InvalidArgumentException("Invalid age to weight ratio: $age : $weight"); } // TODO: other sanity checks here. $this->name = $name; $this->age = $age; $this->weight = $weight; } } $person = new Person('Joe', 22, 100); $person->age = 33; // throws a yet to be named exception -- Edit bug report at http://bugs.php.net/?id=46506&edit=1 -- Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=46506&r=trysnapshot52 Try a CVS snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=46506&r=trysnapshot53 Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=46506&r=trysnapshot60 Fixed in CVS: http://bugs.php.net/fix.php?id=46506&r=fixedcvs Fixed in CVS and need be documented: http://bugs.php.net/fix.php?id=46506&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=46506&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=46506&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=46506&r=needscript Try newer version: http://bugs.php.net/fix.php?id=46506&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=46506&r=support Expected behavior: http://bugs.php.net/fix.php?id=46506&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=46506&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=46506&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=46506&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=46506&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=46506&r=dst IIS Stability: http://bugs.php.net/fix.php?id=46506&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=46506&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=46506&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=46506&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=46506&r=mysqlcfg
