Edit report at https://bugs.php.net/bug.php?id=40837&edit=1
ID: 40837 Comment by: dmittner at llnw dot com Reported by: nick dot telford at gmail dot com Summary: static and non-static functions can't have the same name Status: Not a bug Type: Bug Package: Class/Object related Operating System: Irrelevant PHP Version: 5.2.1 Block user comment: N Private report: N New Comment: @ni...@php.net: While what you write is all technically correct, I think it comes down to this being the problem: ":: is not a "static access operator", it's a "scope resolution operator". It calls a method (or accesses a property) in a certain scope." Conceptually that one operator is trying to do too much. That "certain scope" it's trying to use isn't chosen by the programmer; it's chosen by the context; by where it's being used. That's presumptuous and an unnecessary limitation. "::" is (AFAIK) the only way to access specifically static resources in one context, but then is also used to reference the resources of special names in other contexts. Clearly people want to be able to call the same method name in both an object and static scope. It's the same reason people like function overloading: they have logic that accomplishes the same goal but done differently--this time based on scope. And we'd rather not dirty our code with resource names named differently just to identify scope. If the :: operator can't consistently serve this purpose because it's also having to accommodate "parent" and other special names, then maybe we just need a new operator specifically for calling methods in a static scope and ONLY for doing that. The more I think about this the more I think :: is just broken because it's treated inconsistently. There's probably good reasons I'm not thinking of, but it seems :: could have always meant "static scope" and "->" could have always meant "object scope"; and "parent->resource" would have been valid right alongside "parent::resource", each accessing the parent's resource in legitimately different scopes. So leave :: as it is for backwards compatibility. Add support for "->" on special names for object scope and a new operator specifically for static scope. Then we'll be able to define both object-scope and static-scope versions of the same resources and we'll have operators to access each consistently. Ultimately it's not a huge deal. It'd just be nice to be able to use the same names in both scopes. But we can at least achieve the functionality for now by naming everything "$staticVariable" and "staticMethod()". It's just really gross. Previous Comments: ------------------------------------------------------------------------ [2013-04-21 09:40:32] ni...@php.net We *can not* have static and non-static methods with the same name. This is *not* just a backwards compatibility concern. I think the issue here is that you got the meaning of the :: operator wrong. :: is not a "static access operator", it's a "scope resolution operator". It calls a method (or accesses a property) in a certain scope. E.g. Foo::bar() calls the method bar() in the scope of class Foo. bar() here can be any method. A "static" method just means that the method does not need $this. The Foo::bar() call will only work if a) the method is static or b) the method is non-static and we have a $this. The distinction between "static access operator" and "scope resolution operator" is important and helps you understand why some things are as they are. For example, if you want to access a parent method, then what do you write? parent::foo(). This means that you call foo() in the parent scope. I get that people might argue whether "calling non-static methods with ::" is useful in the general case, but calling parent methods is something everybody should understand and find useful. And using that example it's also easy to see why you couldn't have the same static and non-static method. Consider this small example: class A { public function foo() { echo 'non-static'; } public static function foo() { echo 'static'; } } class B { public function bar() { echo parent::foo(); } } (new B)->bar(); // What do you get? Allowing static and non-static methods of the same name would require us to completely change the concept of scope-resolution and find a different way to call parent methods etc. So, just to say it again: Removing "::"-calls to non-static methods is *not* just a backwards compatibility issue, it would also cause problems with other, currently used and encouraged language features. Another thing that might help the understanding (apart from interpreting :: as scope-resolution) is not seeing static and non-static methods as distinct method types. Rather they are the same and "static" is just another method modifier like "public" or "final": You probably wouldn't ask to have "an abstract method and a final method of the same name", right? Asking for a non-static and static method of the same name makes similarly little sense. "static" just means "doesn't need $this" and nothing more. On a related note, this "static" modifier is also available for closures (i.e. you can write "$foo = static function() { ... }") and also means the same there, that the closure does not need $this. Prefixing a closure with "static" does not make it some kind of wholly different function type, it's just a modifier. Same for the static methods ;) I hope things are a bit clearer now. ------------------------------------------------------------------------ [2013-04-21 05:30:23] dmittner at llnw dot com I've got to add my vote to this feature. My use case consists of data validation methods. If called statically the validation tests are limited to things like string length, contents, etc. If called on an object it would include those tests (probably calling the static form of itself) and also comparative tests to other object conditions. I sympathize with backwards compatibility but sometimes you have to push forward. Case and point, some people I know are working with a Java-based system that doesn't support Java 7, so when building new servers they have to explicitly install an older version. Cutting a line between major PHP versions seems similarly viable. I'd also cite Magic Quotes which are completely removed in 5.4, which could similarly break older PHP4 compatibility. The precedent is set. Failing all that, how about a configuration option? ------------------------------------------------------------------------ [2012-11-20 02:13:10] capitaine dot gloumi at gmail dot com The "backward compatibility" should set to deprecated any static call of object method, and use it IF NO static method with the same name exist. I use static method and object method with same name in lot of paterns, it's useful in lot of case. ------------------------------------------------------------------------ [2012-11-19 03:27:35] ahar...@php.net If a class is namespaced, by definition it isn't PHP 4 compatible. ------------------------------------------------------------------------ [2012-11-15 23:23:31] jpmarois at hotmail dot com ahar...@php.net: Sure, go Microsoft's way and move forward by staying behind for the sake of "compatibility". Please explain why, "As of PHP 5.3.3, methods with the same name as the last element of a namespaced class name will no longer be treated as constructor.". If PHP wont even initialize a "compatible" PHP 4 class anymore, how is it relevant to preserve instance methods being called statically? ------------------------------------------------------------------------ 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=40837 -- Edit this bug report at https://bugs.php.net/bug.php?id=40837&edit=1