Question

I have two methods -a and -b.
-a calls sometimes -b, and -b sometimes calls -a. Both methods are intended to be private, and not called from outside.

But I had to make one of them public in the .h file, because otherwise the compiler would go crazy and give a warning for either one of them.

Is there any valid and good-practise solution for that problem?

Answer 1

Traditionally, what you’d do is define a category (something like @interface MyClass (MyClass_Private) inside the implementation file that declares the private methods. Apple recently introduced a feature called a class extension that is intended for this exact case. It’s basically a specialization of a category, but the class has to implement the methods when it’s first defined. It looks like:

@interface MyObject ()
    - (void)setNumber:(NSNumber *)newNumber;
@end