Like I said before, the factory and singleton patterns are just example
applications of this mechanism.
Right, but I'd like to see why we *need* it - i.e. what it allows to do that other things don't. I'm afraid that we might have a case of featuritis here (not meaning this specific proposal, I'm talking more in general state of affairs) in 5.3 - we will turn PHP from simple language into minefield of magic methods where you can't possibly know what the code you are looking at actually does. It might be useful for some applications but might hurt the language as a whole. It also can have a lot of implications what have unintended - i.e. how typehints are supposed to work with this? How reflection and autoloading would work? What with static methods and variables?
What I want to use them for in PHPUnit is improving the Mock Objects
system.
As far as I know, Java has unit tests but doesn't allow replacing classes. How does it work in Java?
I hope this makes my motivation for the feature more clear.
Yes, I can see the motivation now, but I'm not entirely convinced allowing to replace classes with other classes would be the best solution. I know there are OO languages extensively using unit testing and not having this feature - I'd propose looking into how it is done there.
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Stanislav Malyshev, Zend Software Architect
stas@zend.com http://www.zend.com/
(408)253-8829 MSN: stas@zend.com