nil vs kNilOptions

Question

I find some time ago the enum kNilOptions which is equal to 0. I try to make my code the most readable but I wonder what is best to use when you have methods that take an option parameter, for example :

[NSData dataWithContentsOfFile:imageURL.path
                               options:kNilOptions
                               error:&error];

I usually see nil in a lot of code I read but I think kNilOptions would be more accurate. I don't see often (almost never) kNilOptions. Is there a reason for that?

Do you think it is ok to use it or is it better to stick to simply nil?

Answer 1

I think 0 is more readable than kNilOptions and there is some evidence that kNilOptions is "old".

You should use nil to represent uninitialized Objective-C object references and NULL for uninitialized C pointers (void *, char *, etc).

Use 0 if the options doesn't provide a "none value", which is the case for options NSDataReadingOptions.