Translating operator== in C++ to Objective-C

Question

I am transcribing some C++ code into ObjC. The operator==() that I am looking at compares its private members one-by-one and returns true iff they are all true.

What is the equivalent implementation of operator==() in ObjC?

From browsing, I see in ObjC:

• -isEqual
• -isEqualTo
• -isLike
• == (built-in? not overrideable?)
• any others I missed?

What is the protocol for these methods? (deep or shallow comparison, etc...?) Which one should I be using to replace an operator==() that compares all its members?

Answer 1

isEqual: is likely what you want to override. Also ensure that hash returns the same value for two objects that are equal.

There isn't really a protocol for comparison. Do whatever makes sense for your class. If you're comparing all members in your operator==() then that'd be deep comparison and yes, use isEqual: .