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Date: Sun, 13 Jul 2014 16:17:11 +0100
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Subject: Re: [PHP-DEV] [RFC] Scalar Type Hinting With Casts (re-opening)
From: rowan.collins@gmail.com (Rowan Collins)

On 13/07/2014 15:59, Jocelyn Fournier wrote:
> From my point of view, if the type annotations are doing implicit cast 
> (with or without E_NOTICE/E_STRICT warning), they should behave 
> exactly the same than an explicit cast. If it behaves differently, 
> I'll be really difficult for a developer to guess what will be the PHP 
> behaviour with this new syntax.

The problem is, in PHP an explicit type cast never fails - (int)'abc' 
simply gives you the value 0, not an error. If you let scalar typehints 
just generate unchecked casts, we'd have this:

wants_object(object $foo) { var_dump($foo); }
wants_int(int $foo) { var_dump($foo); }

wants_object('abc'); // fails with E_RECOVERABLE_ERROR
wants_int('abc'); // succeeds and prints int(0)


That seems both inconsistent and less useful than a hybrid juggling + 
validation approach.

-- 
Rowan Collins
[IMSoP]