[fpc-devel] {$Interfaces Corba} and TInterfacedObject

[Graeme Geldenhuys]

Hi,

I previously asked what is the difference between the supported
$Interfaces types. eg: Corba vs COM.
>From those replies, they are very much the same, except that Corba
interfaces are NOT reference counted.

So what do I use to create interfaces and classes that implement interfaces?
Which declaration style do I use?  Or doesn't it make a difference?

type
  ICommand = interface(IInterface)
  vs
  ICommand = interface(IUnkown)
  vs
  ICommand = interface


Now for created classes that implement those interfaces. What base
object do I use?

type
  TCommandClass = class(TInterfacedObject, ICommand)
  vs
  TCommandClass = class(TSomeCustomNonReferenceCountedClass, ICommand)


I can't imagine that usig Corba style interfaces that I'm allowed to
use TInterfacedObject as a based class, because TInterfacedObject
implements reference counting.  Is there some other base class I'm
supposed to use with Corba style interfaces?


Does FPC have a Non-Reference counted base class already?  It's quite
simple to implement you own, but is stupid if FPC doesn't already have
one.


Also, do I have to specify {$Interfaces Corba} in every unit I have,
or is it only needed in the using that defines the interface itself?
Basically, is that compiler setting unit based or project (global)
based.  Why I ask, is because {$mode xxx} is unit based, not global
across my whole project.  So can I mix Reference counted and
Non-Reference counted interface styles in the same project?

I found find any help referencing these issues.... The help topics on
interfaces and $Interfaces styles are very vague.

Regards,
  - Graeme -


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