C++ (Qt) plugins. Pimpl. How to leave a public .h file to hide the class implementation from plugins?

Question

C++ / C#

Greetings.
The program uses a plug-in system with interaction through a signal/slot, i.e. I can pass QObject * if necessary.
Now we need a subject.
Those. plugins can include the .h class file, I would like the class implementation (.cpp) to remain unknown for them, since it may change in the future.
Those. simply passing a reference to a class is naturally not suitable.
I am familiar with pimpl, but I can’t adapt it for plugins, and I don’t think it’s quite suitable.
Or will it fit? Is there a code example somewhere?
Or can someone tell me at least in what direction to move?
Or "Son, this is fantastic"?

Answer 1

Made.
In a class, function calls go through a wrapper that calls a function pointer.
header:

DB& Exec() { return (this->*exec)(); }
 DB& (DB::*exec)()= &DB::_Exec;
DB& _Exec();

I pass a link to the class to the plugins.
But you have to write each function in three places, but it works.
It may be possible to simplify in the future.