Is it wrong to use int in Cocoa and CocoaTouch?

Question

What is the advantage of using something like NSInteger instead of int in code? I see this in examples a lot, including Apple's official code samples.

Answer 1

I am pretty sure that NSInteger and NSUInteger were invented to solve 64-bit quantization issues on Mac OS (they are guaranteed to be the right size, no matter what architecture you are building for). I don't think it matters what you use on the iPhone, though I would get in the habit of using Apple's NS-types.

Anyway, if you ever port your code to Mac OS, it will be easier.

Answer 2

There's a similar question here on SO.com: http://stackoverflow.com/questions/13725 I prefer using NSInteger because it's future-proof, Apple now uses it over int, and it's the recommended way of doing things.

But it's not "wrong" to use int.

Answer 3

• In 32-bit code (including the iPhone): int is 4 bytes, long is 4 bytes, pointers are 4 bytes
• In 64-bit code: int is 4 bytes, long is 8 bytes, pointers are 8 bytes

Many existing APIs (incorrectly, for historical reasons) used int in 32-bit mode but must use long in 64-bit mode.

In C, int and long are not equivalent types, so if you use int you may be incompatible with the 64-bit API, and if you use long you may be incompatible with the 32-bit API. By using NSInteger your code will be compatible with both 32-bit and 64-bit versions of these APIs.

So if you're using an API that specifies NSInteger, then you should use NSInteger.

In your own code and your own APIs:

• If you need a 4-byte integer, use int
• If you need a pointer-sized integer, use long or NSInteger
• if you need an 8-byte integer, use long long

The reason you wouldn't necessarily use NSInteger for everything is that 8-byte integers are overkill for many purposes.