Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:111157
To: internals@lists.php.net
References: <alpine.DEB.2.23.453.2007221247530.7489@singlemalt.home.derickrethans.nl>
Date: Thu, 23 Jul 2020 17:36:22 +0100
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Thunderbird/68.10.0
MIME-Version: 1.0
In-Reply-To: <alpine.DEB.2.23.453.2007221247530.7489@singlemalt.home.derickrethans.nl>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-GB
Content-Transfer-Encoding: 7bit
Subject: Re: The @@ is terrible, are we sure we're OK with it?
From: marandall@php.net (Mark Randall)
Message-ID: <php.internals-111157@news.php.net>

On 22/07/2020 13:00, Derick Rethans wrote:
> - There are lots of grumbles, both on here, room 11, as well as in the
>    wider community (https://www.reddit.com/r/PHP/comments/hjpu79/it_is/)

 From discussions in R11 I want to offer the following example of why 
either option with a closing tag is preferable to allow maximum 
flexibility in future development.

Assume we want to extend attributes to include something a lot of PHP 
features have, an access scope, to only allow accessing annotations from 
within the class itself, or a descendant.

Then we end up with something like :

class Foo {
   @@protected Attr protected int $bar;
}

Contrast that to something with opening and closing tags where they are 
clearly grouped:

class Foo {
   #[protected Attr] protected int $bar;
}



What other syntax might we want to add? Perhaps we want to add a way to 
enforce validation at encounter time with a "checked" keyword.

@@checked protected Attr(1,2,3) protected int $bar

#[checked protected Attr(1,2,3)] protected int $bar

It's much less ambiguous what belongs to what.



Now we could dig ourselves out of this hole using additional tokens 
around @@ such as @@(checked protected Attr) but at which point why not 
just use a mechanism that supports it out of the box?

Mark Randall