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Date: Sun, 26 Feb 2012 21:50:56 -0500
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To: =?ISO-8859-1?Q?=C1ngel_Gonz=E1lez?= <keisial@gmail.com>
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Subject: Re: [PHP-DEV] Object Casting - An Alternative to Type Hinting
From: ircmaxell@gmail.com (Anthony Ferrara)

I fail to see how you would do it via a register function...  Unless
you mean a call-chain of callbacks to try to "cast" with a "from" and
a "to" parameter:

spl_autocast_register(function($from, $to) {
    if ($to =3D=3D 'Integer') {
        return new Integer((int) $from);
    }
});

That could have extreme performance penalties, as every callback in
the chain (at least up to a valid cast) would then need to be called
for every single cast operation.

Not to mention that you're now externalizing where the cast happens
into a non-obvious and non-extendable spot (meaning that you're
removing the possibility of modifying behavior via polymorphism)...

I prefer the concept of binding the cast operations (two, for
symmetry) to the class itself, as it localizes the functionality to
that class, and is quite predictable and extendable.

If I missed the point you were trying to make, please elaborate.

Thanks,

Anthony

2012/2/26 =C1ngel Gonz=E1lez <keisial@gmail.com>:
> I just realised that if it were going to add magic casting, it could as w=
ell
> be done with a spl_autocast_register(), so that you could either cast thi=
ngs
> when they match, throw an exception, etc. =A0(there should be some defaul=
t
> value dynamic typing, so the perfomance wouldn't hurt) .
>
> I don't think that's the perfect solution, though.
>