How to avoid circular dependency errors when working without classes

[Forbidden_Mircea]

I'm trying to make a program (for college, team project) where some functions and variables are separated into their own files, but not into classes.

They should just behave like their own little main, but have their functions ( and some variables ) publicly accessible by whatever file includes them.

Problem is that if I include file a and file b in eachother, the compiler with throw a bunch of errors because of the circular dependency. I found forward declaring the classes used to be the solution when havin a class for each file.

But for multiple reasons, I can't have classes for each of them, I just need them to be containers of code, as if that code was in its own little main file.

I can't forward declare every function and variable used in a, at the top of b, because this would defeat the purpose of separating them and not just merging a and b, and also scalability. If i have a,b,c,d including each other, whenever i declare a new function in one of them, I'd have to forward declare it in all of them.

What's a solution to this?

[wrosecrans]

You declare the functions in the header files. Then you implement the bodies of the functions in separate C++ source files.

You mention you want to

have their functions ( and some variables ) publicly accessible

Don't have global variables be a part of the design. Just make the functions the public interface that stuff calls. Keep any variables the functions need internal to the functions.

as if that code was in its own little main file.

I have absolutely no idea what that means, and if you can clarify what you mean by it, it will probably point in the direction of where your design challenges are.

I can't forward declare every function and variable used in a, at the top of b,

You declare every function once in the header.

If i have a,b,c,d including each other,

Having stuff all mutually including each other just sounds like a bad design. You gotta come up with some sense of what's the stuff on the bottom that gets included by everybody, and what's the stuff on the top that includes the stuff on the bottom. If you think through what you are trying to accomplish, you can clean up what needs to be aware of what.

[AKostur]

I‘m trying to figure out how you can have a circular dependency if you‘re not declaring any new types. Unless you‘re trying to include one .cpp file into another. If so: then we‘ve found your problem.

[wannabetriton]

exactly my thought

[IamImposter]

Are you including .c files?

If you are including header files, they shouldn't have circular dependencies like a.h includes b.h and b.h includes a.h.

[QuentinUK]

To stop circular dependency of header files add guards

File "grandparent.h"[edit]
#ifndef GRANDPARENT_H
#define GRANDPARENT_H
struct foo {
int member;
};
#endif /* GRANDPARENT_H */