Access to Outside Class Definition

[kakhao]

Can I access to public class that is defined in another file as public class?
To be more clear, suppose we're producing a bot - factory(somebotcategory, somebotcodefile).
If we want to get remote control to this bot, we need some public class with static member, that is ok, like in exercises.
But when we are working on code, there is no another bot code loaded, therefore compiler gives error.
Is there any way to get class definition from another file visible? I mean something like #include <someheader.h>.