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Date: Thu, 29 Jan 2015 22:43:00 -0600
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Subject: Re: [PHP-DEV] Use "caller" keyword, to access object caller.
From: larry@garfieldtech.com (Larry Garfield)

On 01/29/2015 10:30 PM, S.A.N wrote:
> I will clarify the benefits of the keyword.
> Single instance of the class can reused in different contexts calls.
>
> <?php
>
> class A
> {
>      public $object;
> }
>
> class B
> {
>      public $object;
> }
>
> class C
> {
>      public function getCaller() {
>          return caller::class;
>      }
> }
>
> $a = new A;
> $b = new B;
> $c = new C;
>
> $a->object = $c;
> $b->object = $c;
>
> $a->object->getCaller(); // return A
> $b->object->getCaller(); // return B
>
> $c->getCaller(); // Fatal Error - undefined caller context
>
> ?>

This seems like an extremely bad idea to do in the first place. Code in 
class C should function the same whether it was called from $a or $b.  
If it should vary, that should be made explicit in the object's 
construction and you have DIFFERENT instances of it.

Having an object that behaves differently depending on an implicit 
relationship with where it happened to be called from is full of all 
kinds of impossible to debug magic.  I don't even know how you'd unit 
test it.  I can think of no use case where this wouldn't cause only 
problems.

--Larry Garfield