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To: Ilija Tovilo <tovilo.ilija@gmail.com>, internals <internals@lists.php.net>
Thread-Topic: [PHP-DEV] [RFC] Shorter attribute syntax
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Date: Thu, 4 Jun 2020 12:39:51 +0000
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Subject: Re: [PHP-DEV] [RFC] Shorter attribute syntax
From: theodorejb@outlook.com (Theodore Brown)

On Thu, June 4, 2020 at 5:37 AM Ilija Tovilo <tovilo.ilija@gmail.com> wrote=
:=0A=
 =0A=
>>> Does the PHP parser prevent us from adopting #[attr]? I presume=0A=
>>> C#'s [attr] syntax and C++'s  [[attr]] are impossible due to=0A=
>>> PHP's short array syntax.=0A=
>>=0A=
>> yes, that would create ambiguity in the parser since `#` (just=0A=
>> like `//`) is for comments.=0A=
>=0A=
> I've mentioned this off-list before. If we consider @@ with a BC=0A=
> break we could also consider #[] by making #[ a symbol.=0A=
> This is also a breaking change but a probably similarly small one.=0A=
> It would break code like this:=0A=
> =0A=
> # Comments still work=0A=
> #[ <-- But they can't start with #[=0A=
> =0A=
> To me both of those look acceptable but #[ looks nicer (but that's=0A=
> just my personal preference).=0A=
=0A=
Hi Ilija,=0A=
=0A=
From the perspective of looks I don't have a strong preference=0A=
between them. There are two main reasons the RFC doesn't propose the=0A=
`#[]` syntax. First of all, I would consider this a larger BC break=0A=
than `@@`. Although hash style comments are relatively uncommon, some=0A=
codebases do use them, and I don't think we can presume to say that=0A=
it "isn't useful" to begin a comment with a `[` (as can be said about=0A=
using multiple suppression operators).=0A=
=0A=
Secondly, the `#[]` syntax is 50% more verbose than the two character=0A=
`@@` proposal; Rust is the only language I found that uses three=0A=
characters for its attribute syntax like this.=0A=
```=0A=
=0A=
Best regards,=0A=
Theodore=0A=