Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:130713
Precedence: list
MIME-Version: 1.0
Date: Thu, 30 Apr 2026 09:43:26 +0200
To: Daniel Scherzer <daniel.e.scherzer@gmail.com>
Cc: php internals <internals@lists.php.net>
Subject: Re: [PHP-DEV] Pre-RFC discussion about adding friendship to PHP
In-Reply-To: <CALaXqqQ-J=_r4X2ENXehU6TDLBbgkuqPk=LguLLEdTYbwmsumQ@mail.gmail.com>
References: <CALaXqqQ-J=_r4X2ENXehU6TDLBbgkuqPk=LguLLEdTYbwmsumQ@mail.gmail.com>
Message-ID: <68afbf850e65a3f07e8b922a9fefa0a8@bastelstu.be>
Content-Type: text/plain; charset=UTF-8;
 format=flowed
Content-Transfer-Encoding: 8bit
From: tim@bastelstu.be (=?UTF-8?Q?Tim_D=C3=BCsterhus?=)

Hi

Am 2026-04-29 19:30, schrieb Daniel Scherzer:
> I haven't started work on implementing this yet, but there is a big
> question about how to indicate friendship that I wanted to get some
> feedback on. Specifically, should it be added with a new keyword, or 
> with
> an attribute?

It should be a proper keyword for the reasons that are also mentioned in 
your blog post: Attributes are not part of the public API and thus do 
not contribute to e.g. LSP checks. They are also expected to gracefully 
degrade when they do not exist, which means that running code written 
with friendship in mind on older PHP versions will silently expose a 
different API instead of failing in a visible way.

See also the reasoning that I provided in the #[\Override] RFC: 
https://wiki.php.net/rfc/marking_overriden_methods#why_an_attribute_and_not_a_keyword. 
I think the related mailing list discussion provides additional context 
- and I seem to remember I wrote something similar in some other RFC 
discussion as well.

Best regards
Tim Düsterhus