objective c - NSString retain Count

Question

Just couple of days i was working on a project and i have to see what is retain count of a string.

But it always return me "2147483647", Why it is so?

Check out this code to check it yourself.

NSString *str = [[NSString alloc] initWithString:@"Hello World"];
NSLog(@"String Retain Count: %i", [str retainCount]); 

So my question is why it is not returning 1 like other objects return, why i am getting "2147483647"

Thanks in advance.

Answer 1

The compiler is smarter than you.

It sees @"Hello world" and thinks "Aha! A constant string!"

It then sees [[NSString alloc] initWithString:@"Hello world!"] and thinks "Aha! An immutable object created with a constant string!"

It then collapses both of them down into a single NSConstantString, which has a retainCount of UINT_MAX, so that it can never be released.