Hi Thierry,

>IMO a prototype-based object model gives you the ability to change the 'base class' on which every instance is based - VFP does not allow that, you need to manually create sub-classes and derive all your classes and objects from them.

The thing with VFP is that its implementation is closer to the prototype side then the class side, the language however is disguised as a class based language. One of the many oddities that makes VFP hard to master for a new developer.

If you store an expression in a property that uses THIS, that reference points to the class object, eg. =MyFunc(This). If you store this reference and later change its properties, you are indeed changing the class. Subsequent calls to CREATEOBJECT() will reduce different instances. I agree that the language isn't supposed to show this behavior.