[kmeisthax]

Copyright law already allows you to copyright specific combinations of unprotectable elements. It's called thin copyright, it's why Katy Parry got sued and lost, and it's software application is called Structure, Sequence, and Organization (SSO). You can in fact claim copyright on all characters that look like Harry Potter, because the standard for copyright infringement is "access and substantial similarity". This is because if your copyright doesn't extend to someone blatantly tracing over your work, then it's not a copyright.

You specifically need to argue that the API itself - the specific combination of types in a specific order, with a given set of Unicode or ASCII characters to identify it - is not copyrightable, not just that it's made up of uncopyrightable things. This is harder, because this same practice in other contexts (e.g. music, literature, and so on) is very much protectable. You need to argue that software is different.