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Date: Mon, 04 Nov 2024 14:16:23 +0100
To: Rob Landers <rob@bottled.codes>
Cc: Larry Garfield <larry@garfieldtech.com>, php internals
 <internals@lists.php.net>
Subject: Re: [PHP-DEV] RFC: Support Closures in constant expressions
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From: tim@bastelstu.be (=?UTF-8?Q?Tim_D=C3=BCsterhus?=)

Hi

Am 2024-11-04 13:33, schrieb Rob Landers:
>> What would you expect the semantics of that script to be?
> 
> Isn't this semantically equivalent to:

Perhaps? That's the question I am asking. Given that this is not a valid 
PHP program as of now, it would as least be debatable how this is 
supposed to work. It gets funnier once you want to support variables in 
the general case (which I consider a necessary companion to support 
variable capturing):

     class Foo {
         public function __construct(&$out) {
             $out = 'out';
         }
     }

     function foo(
         string $bar,
         string $baz = new Foo($bar),
     ) {
         var_dump($bar, $baz);
     }

To be clear: We do not intend to solve this question with this RFC. 
These examples are just intended to highlight the (semantic) 
complexities of supporting variables within const-expr.

Best regards
Tim Düsterhus