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Date: Mon, 2 Nov 2015 09:22:42 +0000
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Subject: Re: [PHP-DEV] [Question] Variadic method signature compatibility
 between 5.6 and 7.0
From: rowan.collins@gmail.com (Rowan Collins)

Alexander Lisachenko wrote on 01/11/2015 21:49:
> class Foo {
>      public static function test($bar = null) {
>          var_dump(func_get_args());
>      }
> }
>
> class Baz extends Foo {
>      public static function test(...$args) {
>          parent::test(...$args);
>      }
> }
[...]
>  From userland point of view, these signatures should be compatible, so I
> decided to check this behavior, was it intended or not.

Should they? func_get_args() can be used to simulate any function 
signature, so you could equally say that the following are "compatible":

class Foo {
     public static function test($foo, $bar, $baz) {
     }
}

class Baz extends Foo {
     public static function test() {
	list($foo, $bar, $baz) = var_dump(func_get_args());
	parent::test($foo, $bar, $baz);
     }
}


Clearly, from the language's point of view, class Baz is missing the 
parameters in its function signature that Foo specifies, so the warning 
seems perfectly correct to me. In your example, you've replaced a single 
optional parameter ($bar = null) with a specification of variadic 
parameters (...$args); these are clearly not interchangeable, so again, 
the signature is different.

Regards,
-- 
Rowan Collins
[IMSoP]