In Objective-C, are int variables that haven't been assigned a value nil?

Question

If I have this in my .h file:

int index;

And then in the .m file I have:

if (index == nil)
         


        

Answer 1

There is no such thing as "nil" for ints. That's an object value. As for what variables are initialized to by default:

• Non-static local variables are not initialized to any defined value (in practice, they will usually have whatever bit pattern was previously in the memory they're occupying)
• Static variables are initialized to 0
• Global variables are initialized to 0
• Instance variables are initialized to 0

Note that the first rule above also applies to local object variables. They will not be nil-initialized for you. (Instance variables with object types will be, though.)