Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:121445
Content-Type: multipart/alternative;
 boundary="------------GcN6CrP7Mj7v4e5TvG0hH5WK"
Message-ID: <91a22e31-a073-4bdb-b78f-48dd70567a37@processus.org>
Date: Mon, 23 Oct 2023 17:27:05 +0200
MIME-Version: 1.0
Content-Language: en-US
To: Larry Garfield <larry@garfieldtech.com>,
 php internals <internals@lists.php.net>
References: <5be74be4-972f-4eae-ae46-6d92587ccc7f@processus.org>
 <78a8a19a-2e00-4437-9c3a-dc069db77426@app.fastmail.com>
In-Reply-To: <78a8a19a-2e00-4437-9c3a-dc069db77426@app.fastmail.com>
Subject: Re: [PHP-DEV] Constructor promoted property and default value
From: pierre-php@processus.org (Pierre)

--------------GcN6CrP7Mj7v4e5TvG0hH5WK
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit

Le 23/10/2023 à 17:16, Larry Garfield a écrit :
> Where this becomes a problem is readonly properties, since those are not allowed to have default values.  (That would make them constants with worse performance.)  A solution would need to be able to detect that the parent::__construct() isn't called, and then call it anyway, or at least partially call it.  Unfortunately, I can think of many cases where such a call would result in unexpected behavior.
>
> It might be possible to resolve, but it's definitely not simple, and it could easily lead to weird behavior.
>
> --Larry Garfield

Thanks for the explanation !

I see, there is no easy answer, yet current state is, in my opinion, 
unintuitive for developers, and eventually unsatisfying when falling in 
this trap.

That's sad that readonly properties make this not trivial. Maybe some 
kind of object construct-post-hook could detect those case and affect 
variables with default values ? I don't know enough PHP internals to 
give a rational answer to this problem through...

Regards,

--

Pierre


--------------GcN6CrP7Mj7v4e5TvG0hH5WK--