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Date: Wed, 16 Jul 2014 20:47:48 +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 15/07/2014 20:44, Andrea Faulds wrote:
> PHP has pseudo-functions, maybe we could use that format? cast_int($foo)?
>
> Actually, perhaps the solution is an ahead-of-time check:
>
>      if (safe_cast($foo, int)) {
>          $bar = (int!)$foo;
>      } else {
>          $bar = 1;
>      }

I think this would be quite nice - keeps things relatively short without 
introducing so much punctuation that it starts looking like a Perl script ;)

The only problem is that either you need a whole set of functions 
(safe_int($foo), safe_float($foo), etc) or you need some format for that 
second argument, which gets you into some odd meta-validation: if you 
take a string, or an integer (expected to be in the form of a constant 
like PHP_INT), then it would be possible to write safe_cast($foo, $bar), 
and now we need rules on validating $bar, and what happens if it's wrong.

The magic form with a keyword like you've written avoids that, but it 
feels kind of weird - like when SQL date functions take things like 
"day" and "hour" as barewords rather than strings.

Maybe I'm overthinking it though.

-- 
Rowan Collins
[IMSoP]