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Date: Thu, 19 Aug 2010 01:13:07 -0700
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Subject: Re: [PHP-DEV] inheritance check too strict?
From: smalyshev@sugarcrm.com (Stas Malyshev)

Hi!

> I was under the impression that, in order for inheritance to provide
> proper polymorphism, overridden methods should share the parent's method
> signature, although they can have additional optional arguments.

Your impression is wrong. Overriden method should have _compatible_ 
signature - i.e. accept any argument set that parent object accepted. 
Nothing requires it to have the same signature.

> Otherwise, if you're passed an ObjChild when you are treating it as an
> ObjParent, you could get unexpected behaviour if it ignores $param2 when
> you decide to specify it. PHP doesn't complain about a programmer

Unexpected by whom? Writer of ObjChild->set() knew how to implement it 
without that parameter, so why behavior would be unexpected?

> passing too many arguments to the function as far as I recall, so this
> sort of bug can be easy to overlook.

How this is a "bug"?
-- 
Stanislav Malyshev, Software Architect
SugarCRM: http://www.sugarcrm.com/
(408)454-6900 ext. 227