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Date: Tue, 15 Dec 2020 10:10:54 +0100
Message-ID: <CAPyj-LCM5Cjh_32a2qoRSqn8Ztqts_UnhcgxOxJcvXnhMS1uqQ@mail.gmail.com>
To: PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Short-match
From: tovilo.ilija@gmail.com (Ilija Tovilo)

Hi internals

> With match this becomes much more concise:
>
> ```php
> $this->handler = function ($var): string {
>      return match {
>          null === $var => 'null',
>          true === $var => 'true',
>          false === $var => 'false',
>          \is_string($var) => '"'.$var.'"',
>          default => rtrim(print_r($var, true)),
>      };
> };
> ```

I suspect most use cases of `match (true)` are exactly for things like
this where you're always comparing the same value but not against
fixed values but "shapes". I think some simple and limited pattern
matching would be useful here.

```php
$this->handler = function ($var): string {
     return match ($var) {
         null => 'null',
         true => 'true',
         false => 'false',
         is string => '"'.$var.'"',
         default => rtrim(print_r($var, true)),
     };
};
```

This would have some significant overlap with the short match proposed
here. Combined with the unclear semantics (strict comparison? loose
comparison? type error on non-bool values?) makes me unsure if we
really need the short match.

Ilija