c++ - Can the overall implementation of a component be divided in two objects? -

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i've seen microsoft com , xpcom, @ least i've read , gathered far, implementations of interfaces in component have in single class derives virtual interfaces. correct? missing?

is there way have multiple objects (possibly in separate dll's) each provide functionality , still able freely transition between them using queryiterface?

what i'm looking have component functionality, still allow external client code create new extensions of component (possibly) new interfaces. ideally should happen without divulging current source of component , implementation.

this should possible, although not supported standard high-level wrappers. of wrappers (atl, mfc, etc.) support mapping com object single class. however, queryinterface allowed return different pointer , calls com object code, first com object load different dll, instantiate different object, , return pointer it's interface (vtable).

it's possible far know, you'll writing lot of low-level glue code yourself.


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