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Date: Thu, 2 Jun 2022 14:17:25 +0200
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Subject: Re: [PHP-DEV] [RFC][Under discussion] Fetch properties in const expressions
From: tovilo.ilija@gmail.com (Ilija Tovilo)

Hi Nikita

> This looks like a reasonable addition.
>
> Could there be any expectation that if -> works, ?-> does as well?

Possibly. The implementation was simple enough so I'll add support for
completeness.

---

Hi C=C3=B4me

> It is not clear to me why this allows using -> on enums but not on other =
objects.

The RFC *does* allow using -> on all objects. From the RFC:

> As mentioned, the primary motivation for this feature are enums. However,=
 the
> implementation for supporting new is identical and I don't believe
> arbitrarily restricting how -> can be used in this context makes sense.

> Can you clarify why the following is not allowed:
>
> <?php
>
> $a =3D new Thing();
>
> class C
> {
>   protected $b =3D $a->var;
>   static $staticobj =3D new Thing();
>   function f($p =3D self::$staticobj->var) {}
> }

`protected $b =3D $a->var;` is not allowed because there can't be local
variables in the context of context expressions. `function f($p =3D
self::$staticobj->var) {}` is not allowed because static variables
aren't supported in constant expressions. Your examples would already
fail today without ->.

Ilija