Constants in Objective-C

Question

I\'m developing a Cocoa application, and I\'m using constant NSStrings as ways to store key names for my preferences.

I understand this is a good idea b

Answer 1

Easiest way:

// Prefs.h
#define PREFS_MY_CONSTANT @"prefs_my_constant"

Better way:

// Prefs.h
extern NSString * const PREFS_MY_CONSTANT;

// Prefs.m
NSString * const PREFS_MY_CONSTANT = @"prefs_my_constant";

One benefit of the second is that changing the value of a constant does not cause a rebuild of your entire program.