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References: <CAPyj-LBfSHyF-_zxFX9UScrmKc2Jo2G-GUwQ24fTqqyzxEc+kQ@mail.gmail.com>
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Date: Wed, 1 Apr 2020 10:37:59 +0200
Message-ID: <CAPyj-LAp8OikvES192+UFdpNjsowxEZiR_64_WmkT1f1VwhbfA@mail.gmail.com>
To: Levi Morrison <levi.morrison@datadoghq.com>, PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC][POLL] Switch expression
From: tovilo.ilija@gmail.com (Ilija Tovilo)

Hi internals

After Levis email yesterday we discussed his suggestions in private. I
did some investigation and did find a way to reuse the current switch
syntax. The main problem of the ambiguity was the empty switch
statement vs expression:

```
// Could be a switch expression or a switch statement with an empty
statement (;)
switch ($x) {};
```

Disallowing the switch expression to be empty solves the ambiguity.

```
// This code throws a parser error
$x = switch ($y) {};
```

It's not optimal but everything else will require significant changes
in the grammar and have other downsides. I updated the RFC
accordingly.

Ilija