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Date: Tue, 29 Apr 2008 17:43:22 +0200
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Message-ID: <200804291743.22503.et@php.net>
Subject: Re: [PHP-DEV] Inheritance/compatibility behavior
From: et@php.net (Stefan Walk)

On Tuesday 29 April 2008 15:34:07 Sam Barrow wrote:

> This will not work, I get an error that the two must be compatible.
> Wouldn't it be a good idea to allow any type hint for a parameter that
> does not specify a type hint?

That would be a bad idea, because it violates a (in my opinion, the) core 
principle of OO: If B inherits from A, anything I can do with A (i.e. pass an 
int to the method go) I can do with B.
http://en.wikipedia.org/wiki/Liskov_substitution_principle

Regards,
Stefan

P.S. Sorry if this pops up twice, used the wrong from: address at first ...