static NSString usage vs. inline NSString constants

Question

In Objective-C, my understanding is that the directive @\"foo\" defines a constant NSString. If I use @\"foo\" in multiple places, the same immutable NSString object is referenc

Answer 1

It is not guaranteed that when using @"foo"in multiple places the runtime uses the same storage for them, and certainly may not be the case across compilation unit or library boundaries.
I would rather use static NSString *string = @"foo", especially with a lot of literal strings.