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Date: Thu, 6 Nov 2014 07:51:53 -0700
Message-ID: <CAFMT4NqGhWj8K9DYMh9Ep4dZJd8ZmANViUBb8+e4DaK7WZCLYg@mail.gmail.com>
To: Dmitry Stogov <dmitry@zend.com>
Cc: Andrea Faulds <ajf@ajf.me>, Stas Malyshev <smalyshev@sugarcrm.com>, 
	internals <internals@lists.php.net>, Nikita Popov <nikita.ppv@gmail.com>
Content-Type: text/plain; charset=UTF-8
Subject: Re: [PHP-DEV] [RFC][Vote] Return Types
From: morrison.levi@gmail.com (Levi Morrison)

On Thu, Nov 6, 2014 at 12:43 AM, Dmitry Stogov <dmitry@zend.com> wrote:
> It's clear, that covariant types are more smart, but not supporting them,
> won't prevent access to more specific type properties and methods.
> We are not C++ or Java, and we don't need to cast objects to more specific
> types.
>
> On the other hand covariance requires all return types to be defined before
> class binding.
> It may be a serious new problem. For example you won't be able to compile
> the following code at all?
>
> <?php
> class A {
>   function foo(): C {}
> }
> class B extends A {
>   function foo(): C {}
> }
> class C extends B {
>   function foo(): C {}
> }
> ?>

I think I have figured out away to do the type checks that would allow
this and current checks to work; I'll report back after some trial and
testing.