Objective-C Is it safe to overwrite [NSObject initialize]?

Question

Basically, I have the following code (explained here: Objective-C Constants in Protocol)

// MyProtocol.m
const NSString *MYPROTOCOL_SIZE;
const NSString *MYP         


        

Answer 1

A variable of type NSString *const will always be initialized before your code runs, assuming we ignore C++ vagaries for the moment:

NSString *const MY_PROTOCOL_SIZE = @"...";

A variable of type const NSString * (the const keyword applying to the guts of the NSString, not its address) can be modified by any code, but cannot have messages sent to it. It defeats the purpose of making it const. Consider instead a global function:

static NSString *GetMyProtocolSize(void) {
    return [[MyClass someStringLoadedFromAFile] ...];
}

Or use a class method:

@implementation MyClass
+ (NSString *)myProtocolSize {
    return [[MyClass someStringLoadedFromAFile] ...];
}
@end

You asked a question earlier about why your const strings wouldn't accept dynamic values--this is because you do not seem to understand what const does to a symbol. You should read up on the meaning of the const keyword in C and should look at another approach to getting your strings if const is not the right one.