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Date: Tue, 7 Apr 2020 17:58:36 +0200
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To: Enno Woortmann <enno.woortmann@web.de>
Cc: PHP Internals List <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] [DISCUSSION] Type casting in array destructuring expressions
From: nicolas.grekas+php@gmail.com (Nicolas Grekas)

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>
> I also like Levi's proposal but for the use cases which lead me to the
> idea for this proposal where I explicitly want to cast values and don't
> check their current types it's difficult to use. I think it serves
> different use cases.
>

My personal pov is that the use case you describe is not sound enough to
require a new syntax; this is still fine and explicit (borrowing from one
of your examples), especially considering the weak points noted by Rowan:
$now = (int) $a[0];
$future = (int) $a[1];

The huge benefit of Levi's proposal is that it works with any types, not
just the castable ones: any class/interface would fit there. This means
this new syntax would provide another "type barrier" that could help the
engine or any type analyzer get a better understanding of the variables at
hand.



> You mention the syntax looks weird to you. How would you design the
> syntax if you want to cast the values instead of type checking them?
>

I would abstain from trying to answer then.

I now understand you had this different use case in mind, so I would
totally understand that in turn, you'd be not interested in working towards
Levi's proposal. On the other hand, I would so much like you'd be :)

Cheers,
Nicolas

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