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Date: Sun, 12 Apr 2020 14:47:47 +0200
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To: php internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [DISCUSSION] Match expression
From: tovilo.ilija@gmail.com (Ilija Tovilo)

Hi Iv=C3=A1n

> Would be posible for blocks to require a return statement instead of rais=
ing an error?

It would be possible for the blocks to return values (though not with
the return keyword). I've created a small prototype a few weeks ago:

```
$result =3D match ($x) {
    0 =3D> {
        echo 'Foo';
        echo 'Bar';
        'Baz'
    },
    ...
};
```

https://github.com/php/php-src/compare/master...iluuu1994:block-expression
Heavily inspired by Rust:
https://doc.rust-lang.org/reference/expressions/block-expr.html

While this would perfectly solve the problem perfectly it feels a
little foreign in PHP. Either way, this is something that can be
discussed an implemented in a separate RFC.

> Would be feasible for the fallthrought problem to use =E2=80=9Ccontinue=
=E2=80=9D when you really want to chain =E2=80=9Ccases=E2=80=9D?

Yes, that would be feasible. I personally just don't see a huge
benefit of fallthrough. If we ever implemented pattern matching it
could become unfeasible again (or at least require additional sanity
checks):

```
match ($value) {
    Foo { foo: $foo } =3D> {
        fallthrough;
    }
    Bar { bar: $bar } =3D> {
        // $bar is unbound
    }
 }
```

Ilija