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Date: Sun, 11 Jul 2021 16:02:42 -0300
Message-ID: <CAEsg9X2um5q7rO=0UFpnwQNJO0QOisuVqhL5Ov5-H5xrOb09Hw@mail.gmail.com>
To: Max Semenik <maxsem.wiki@gmail.com>
Cc: Internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] Type casting syntax
From: david.proweb@gmail.com (David Rodrigues)

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I really like the casting syntax, but I think it is difficult to be
approved, at first, because there is already a "clearer" method for doing
something like that. Which for me, particularly, does not invalidate an
alternative.

My suggestion is to create a magic method like __cast(AllowedTypes $in):
self. Eg. __cast(string|int $in): BigNumber. Where AllowedTypes are the
classes allowed to be casted from (or "mixed").

So:

$bn =3D (BigNumber) '123';
$date =3D (Carbon) $date;
$timestamp =3D (Carbon) (int) $date;

I also wanted it to be possible to use a nullable cast, but the idea didn't
go forward (even though there were no alternatives). :(


Atenciosamente,
David Rodrigues


Em s=C3=A1b., 10 de jul. de 2021 =C3=A0s 06:10, Max Semenik <maxsem.wiki@gm=
ail.com>
escreveu:

> I've been thinking about extending PHP's cast syntax to user-defined type=
s,
> e.g. not only (int)$foo but also (MyClass)$foo. Currently, a T_STRING in
> parentheses is always treated as a constant - would it be acceptable to
> hijack this syntax when used in unary operation context, i.e. "(" T_STRIN=
G
> ")" expr? If not, any other alternatives?
>
> --
> Best regards,
> Max Semenik
>

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