I think you are right about separating the ObjC. C++ and ObjC don't play so well together, either, so if your primary language was C++, I think you'd need a plan around how to deal with ObjC.

gcc and clang can handle mixed Objective-C and C++ in a single source file (some call it Objective-C++). The only tricky part is linking since C++ and ObjC++ use a different symbol name convention than C/ObjC; but you can still link between them by using extern "C" declarations in the right places.

Ever heard of Objective-C++? It is also supported by Objective-C compilers.

The problem is that C++ and ObjectiveC have overlapping purposes. The issue isn't that it's impossible to use them together. The issue is that you will have to have a strategy for dealing with conflicts before they occur.

That is true. Actually such considerations should be part of any mixed language project, specially in the presence of portable code.