[fpc-devel] Object upgrades

[Ryan Joseph]

> On Jun 10, 2019, at 4:07 PM, Sven Barth via fpc-devel <fpc-devel at lists.freepascal.org> wrote:
> 
> Of course the dereferentiation of PBase while always have the size of TBase. That's the point of a pointer. You need to add a static Create method to each subclass if you want to use that concept. And no kind of TClassSelf or whatever will help you there as you'd need virtual class functions for that and objects don't support those just as they don't support a "class of" kind of type. There's a reason why classes are superior in nearly all cases after all. 
> 

Got it. That aside the operators are the important thing anyways.

Another question. I’m not sure it’s possible but I did try to add management operators to objects and found that if a initialize operator was declared in a unit which was precompiled and then inherited from an object in another unit which declared another initialize operators, the initialize operator would be called twice.

The issue is that the operator is compiled into some other code which always gets called when the object is used as a var type. Is there any work around to that? The options I’m aware of are:

1) don’t allow management operators in objects (that would be very unfortunate indeed).
2) don’t allow subclasses to redeclare a management operator (that seems ok since the operator can call a virtual method from the base class).
3) allow overriding of operators. I don’t think that would be make sense or perhaps even possible.

Regards,
	Ryan Joseph