Comments on: Building proxies, decorators and delegates in PHP5

By: paul

paul — Wed, 26 Jul 2006 15:51:26 +0000

While I think that proxying functions from more then one base object in one environment IS VERY useful when dealing with shared environments I beg you specify this explicitly. IE: This is a shared environment programming pattern do not use it to draw circles…

Can’t really se any true and undenyable reason to use these techniques while not invoking the all-to-well-known -”not my code, have to go round” reason, which is by the way just a sign of very poor analysis and granulation skills.

Other then that nice tute. - and I like the oracle halo of the company

By: Mike Lively

Mike Lively — Tue, 04 Jul 2006 15:54:22 +0000

This can be worked around very easily by making the base class and all of it’s decorators extend a parent interface. Using __call does mean that the interface will probably have to be empty. (That is unless you create a seperate interface for each method/group of methods that you anticipate decorating. Which gets cumbersome.)

By: Dennis Pallett

Dennis Pallett — Tue, 04 Jul 2006 10:06:49 +0000

You’re right about that, although it shouldn’t really matter that ItalicHelloWorld has its own state.

By: Ivo Jansch

Ivo Jansch — Tue, 04 Jul 2006 09:39:02 +0000

That is indeed correct, this would make the interface the same. However, in your solution, the ItalicHelloWorld would have its own state, meaning that doSomethingElse() would work on member variables of the ItalicHelloWorld instance and not on member variables of HelloWorld instance. (the difference between $this->m_member and $this->m_object->m_member)

Unless you reimplement all methods, which is the point of this article; using the AutoForward baseclass, you won’t have to do that.

Also have a look at the security example near the end. It is applicable to virtually any class, which wouldn’t be possible if SecurityAspect would inherit from one of them.

By: Dennis Pallett

Dennis Pallett — Tue, 04 Jul 2006 09:25:12 +0000

Yes, you can, both child classes extend the HelloWorld class, and you can still use the decorator pattern, i.e.

$obj = new ItalicHelloWorld(
new BoldHelloWorld(
new HelloWorld()));

By: Ivo

Ivo — Mon, 03 Jul 2006 22:13:02 +0000

Thanks, I’ve corrected the samples. Still doing too much PHP4 I guess

By: Andrew Bidochko

Andrew Bidochko — Mon, 03 Jul 2006 21:55:23 +0000

Why are you using assignment by refernce ($obj = &new HelloWorld())?
It has been deprecated in php5.

By: Stephan Schmidt

Stephan Schmidt — Mon, 03 Jul 2006 21:48:41 +0000

The big problem with this approach is, that is will not work if you are using instanceof or type hints in your code.

By: Ivo

Ivo — Mon, 03 Jul 2006 21:40:13 +0000

That is explained near the end of the post; because you cannot have something that is both bold and italic that way.

By: aurelian

aurelian — Mon, 03 Jul 2006 21:34:12 +0000

So, you can write your own wiki syntax now