Edit report at https://bugs.php.net/bug.php?id=46506&edit=1
ID: 46506 Comment by: dave at shax dot com Reported by: glideraerobatics at hotmail dot com Summary: readonly attribute for (public) class variables Status: Open Type: Feature/Change Request Package: *General Issues PHP Version: 5.4 Block user comment: N Private report: N New Comment: 'readonly' property as described here would be extremely useful to me in daily development. Doesn't need to be fancy. The most obvious functionality, as described by others above, is exactly what I want. At the moment, I duplicate this functionality in 90% my classes using __get(). There's presumably a bit of a performance knock in doing it with __get() (never benchmarked it, but it seems obvious) - not routing the read requests for each property through __get() or a separate getter function saves a function call and would be faster. Because I currently use __get() on nearly every major object in my application, I could easily save several hundred function calls per request, which is probably creating a measurable difference in page generation. It may seem CRAZY to accept performance slowdown for something this trivial, but for me having each object defined as an individual solid API in its own right makes my code much more stable, and in a large application prevents unwanted/accidental interference from outside modules. It's mainly about being SUPER sure I've internally validated all data that's entering each object - hardening it! At the moment my options are to make it writable by anyone, or accept a performance hit - this is why I'm very keen for this to be added to the language! For the implementation of this, I'd want it to be like 'protected', not 'private' wherein other classes that inherit the property can also write to it. Previous Comments: ------------------------------------------------------------------------ [2013-03-31 09:09:16] glideraerobatics at hotmail dot com @stian dot pedersen at gmail dot com A "property" keyword isn't good enough because you still need the scope keywords public and protected at least. That's why I used the C# convention in the 1st post. ------------------------------------------------------------------------ [2013-03-30 18:40:43] stian dot pedersen at gmail dot com This feature is seconded. Basically it would be useful to have a modifier which allows internal modification but disallows public reassignment. By an example, letting "property" be the new key word, class Order { property $customer; } class Order { private $customer; public getCustomer(){return $this->customer;} } $order->customer and $order->getCustomer() could have the same semantics in that a "copy of the pointer" in C terms is returned and you cannot call $order- >customer = null any more than you could call $order->getCustomer() = null. However, $customer itself should be modifyable, for instance, $order->customer- >id = 1000, if id is declared as public. This would be more in tune of mat dot barrie at gmail dot com and very useful in OOP. Inside the class, I would prefer to be able to reassign customer at will (even after constructor). Syntactically it would be nice to chose a syntax that would allow support for setters also, but for now, I would be happy with this. It sorta does the same thing as the __get() trick but does not mess up IDE support and will probably execute faster. ------------------------------------------------------------------------ [2012-11-27 15:55:04] info at strictcoding dot co dot uk +1 for this awesome feature. Any reviews from the PHP team? ------------------------------------------------------------------------ [2012-09-18 21:53:20] mat dot barrie at gmail dot com As a point of interest, the C# readonly keyword mentioned actually does not protect exposed classes from being modified, it prevents assignment. So from your example if you duplicate the C# behaviour, this is what it actually would work like this, which I don't think is what you're asking for: -- $count = count($parent->children); // You can do this $name = $parent->children[0]; // You can even do this $parent->children[0] = "BILLY"; // You can still do this $parent->children[] = "BOB"; // And you can still even do this $parent->children = NULL; // But not this unset($parent->children); // Or this -- A readonly attribute probably isn't what's needed here (after all, you're not actually asking for a property that can be made readonly) but instead if the protection level could be defined on the getter and setter independently, so that set could be defined as private and get as public. __get and __set sort of do this, but they're useless if you're serialising, hurt performance, and unless I'm missing something you can't add phpDoc comments to the exposed pseudo- properties. ------------------------------------------------------------------------ [2012-01-25 08:11:40] glideraerobatics at hotmail dot com Changed affected PHP version. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=46506 -- Edit this bug report at https://bugs.php.net/bug.php?id=46506&edit=1