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In-Reply-To: <CA+9eiLsjjFqzg8pwNkwVkq_+YS+RgWWmH8T4eVy-4ORKrZ1rsw@mail.gmail.com>
Date: Thu, 6 Nov 2014 15:15:55 +0000
Cc: Levi Morrison <morrison.levi@gmail.com>,
 Stas Malyshev <smalyshev@sugarcrm.com>,
 internals <internals@lists.php.net>,
 Nikita Popov <nikita.ppv@gmail.com>
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To: Dmitry Stogov <dmitry@zend.com>
X-Mailer: Apple Mail (2.1990.1)
Subject: Re: [PHP-DEV] [RFC][Vote] Return Types
From: ajf@ajf.me (Andrea Faulds)


> On 6 Nov 2014, at 15:08, Dmitry Stogov <dmitry@zend.com> wrote:
>=20
> Use A or B for return type in B::foo(). It'll lead to compile error =
anyway (Class C is not defined).
> It's not possible to compile this by design.

Ok, let=E2=80=99s try this:

<?php
class A {
  function foo(): C {}
}
class B extends A {
  function foo(): B {}
}
class C extends B {
  function foo(): C {}
}
?>

I don=E2=80=99t think this can=E2=80=99t be compiled. When you get to B, =
you know that A doesn=E2=80=99t extend anything, and B doesn=E2=80=99t =
extend C, so C can=E2=80=99t possibly be a superclass of B, and it would =
fail, right?

--
Andrea Faulds
http://ajf.me/