Possibility to undeclare types?

[Weeena]

We consider using ponder in the following way: Assume that our application should be extensible. Further assume that extension clases should derive from a base class that is declared by our application. We would like to use the extension classes in connection with ponder in the following way:

• Load some dll containing an extension class. When the dll is loaded, the dll has to declare the extension class to ponder.
• Knowing the extension class's ponder name (through some meta information like an XML file containing a description for the dll) we let ponder construct an object of this class and cast it to our base class. We make use of this object by calling the base class's virtual interface functions.
• After we are finished using that extension object, we would like to destroy it and unload the dll. When we work as described, we get an exception when our application exits. (We do not get the exception at application exit if we do not unload the dll.) It seems to us that in the destruction code of ponder it is tried to destruct something that has recided in the dll but is now not anymore available since the dll has been unloaded. What could be a solution to this problem? Is there the need for the possibility to explicitly undeclare types?

[billyquith]

If you have definitely deleted all of the objects created by the DLL them this might be a destruction order problem. E.g. the DLL's memory is destroyed before Ponder and some corruption occurs. As you say, it would make sense to unregister things before terminating the app.

[billyquith]

Undeclared is added in v1.1.

[Weeena]

Thank you very much for your quick response to our issues. We have successfully verified that both issues (#16, #21) are working as expected in V1.1.

We are still evaluating if we can use ponder in one of our applications. Unfortunately, it seems that we would like to use ponder for something it was not designed for. Nevertheless, I hope you don't mind if we possibly open some more issues that describe our wishes to ponder.

[billyquith]

I'm interested in having a pragmatic library. I currently don't need this functionality, but I can see how it would be useful. If you have any further suggestions please open another issue ticket.