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Date: Thu, 14 Apr 2016 10:25:07 +0100 (BST)
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To: Lin Yo-An <cornelius.howl@gmail.com>
cc: Levi Morrison <morrison.levi@gmail.com>, 
    internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Union Types
From: derick@php.net (Derick Rethans)

On Thu, 14 Apr 2016, Lin Yo-An wrote:

> On Thu, Apr 14, 2016 at 5:12 PM, Derick Rethans <derick@php.net> wrote:
> 
> > I think what I am missing in the RFC is behaviour with scalar (weak)
> > typehints, and which type the variable in a class would be converted to.
> > Take for example:
> >
> > function foo(int|bool $var) { echo get_type( $var ), "\n"; }
> >
> > foo(5);     I guess int(5)
> > foo(false); I guess bool(false)
> > foo(0.5);   It could be either int(1) or bool(true)
> >
> > And what if the hint would be "bool|int" ?
> 
> I think type conversion shouldn't be done internally, implicitly.
> 
> Implicit conversion leads more confusion in the language. when you 
> pass variables, you have to remember these conversion rules.

Sorry, we already have this with our weak scalar types. You can't make 
union types not work with that.

cheers,
Derick