I'm refactoring some Objective-C code to inherit from a new Swift super class. This has been going okay, and I've been cleaning up build errors as I spot them (some auxiliary enums caused enum name changes, etc.).
But my last error seems to be that I can't subclass the Swift class: "Cannot subclass a class with objc_subclassing_restricted attribute". I didn't notice it before, and all the online references that say you can't subclass a Swift class point to a Swift document that no longer mentions that. They also don't say what they mean by "Swift" class (e.g. is it not marked with @objc?).
In any case, my Swift class looks like:
Camera : NSObject
And my ObjC class looks like:
MCPCamera : Camera
I feel like this is a reasonable thing to try to do. Is it just not possible?