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Date: Wed, 17 Feb 2016 23:16:41 +0530
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Subject: Class constants on object references have variable-inconsistent accessibility
From: kelerest123@gmail.com (=?UTF-8?B?SmFrdWIgS3Viw63EjWVr?=)

Dear internals!

I have encountered an inconsistence, or rather a bug, in PHP's syntax.
The thing is, in PHP you can access constants defined on a
class using reference to an instance of this class, stored in
variable. So we have a code:

<?php

class B {
    const C = 4;
}

$b = new B;
var_dump($b::C === B::C); // bool(true)

?>

Which will nicely pass. But things will go wrong having a code trying
to access the same constant on an object of B stored in member
variable of class A -- let's see below:

<?php

class A {
    /** @var B */
    public $b;
}

$a = new A;
$a->b = new B;
var_dump($a->b::C === B::C); // Parse error: syntax error, unexpected
'::' (T_PAAMAYIM_NEKUDOTAYIM) in...

?>

Let me conclude that if there's access to class' constant using a
reference to an instance of the class, it should be possible with any
type of value-holder (so-called variable).

-- 
Cheers,
Kubis