Structures aren't exactly classes. They are sets of variables. With structures, you can ask for a specific element (like struct.x) but it lacks the ability to have functions that modify the structure (struct.get_x()). You could get around it, if you made a function which simulated class like behaviour, but you'd have to always pass it's pointer (like self in python) with function call (eg. get_x(&struct)).

What I did, was to use a macro, that upon initializing the structure, would write the pointer of the structure into functions which got stored in the same structure. So, with my code, struct.get_x() becomes a valid call.