Best practice on initializing your NSStrings on the iPhone

Question

xCode's "build and analyze" complains about "s" being possible garbage.

Which is the better solution? A, B, or C?

NSString *s;              // A
NSString *s = nil;        // B
NSString *s = @"";        // C

if(x == 1) s = @"you picked 1";
if(x == 2) s = @"you picked 2";
if(x == 3) s = @"you picked 3";

Answer 1

I always go with

NSString *s = nil;

as a default initialization value. It's more sensible than an empty string (an empty string is a "thing", whereas nil is an unknown value), and since you can message nil in Objective-C it (generally) doesn't cause big problems if I somehow forget to give it a "real" value.