Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:111996
MIME-Version: 1.0
Date: Mon, 5 Oct 2020 02:38:01 +0300
Message-ID: <CAFecBuBw1fg89N-ywCOtCi_ETaR=6BRCqNPbJMoUyQTU0u-dxQ@mail.gmail.com>
To: internals@lists.php.net
Content-Type: multipart/alternative; boundary="000000000000e60a5c05b0e0dbc8"
Subject: Literal types RFC
From: bogdanungureanu21@gmail.com (Bogdan Ungureanu)

--000000000000e60a5c05b0e0dbc8
Content-Type: text/plain; charset="UTF-8"

Hello internals,

Since union types have landed in PHP, this allows us the possibility to
have literal types support as well and I would like to hear your
thoughts about an RFC for it.

I think a feature like this would greatly improve the way we model our code
in very common use cases. For example, let's consider having a function
that returns the status of a post.

```php
/**
/** @return "draft"|"published"
*/
function getStatus(): string { }
```

Would become

```php
function getStatus(): "draft" | "published" { }
```

Of course this could become quite messy if there are more than a few
literal types, in which case separate RFCs could be created for type
aliases and valueof/keyof features.

I would also like to mention that I also worked on a basic implementation
for the first phase of the implementation; it's nowhere near to be
completed, but I think I can finish it with some guidance/help from you.

Regards,
Bogdan Ungureanu

--000000000000e60a5c05b0e0dbc8--