On lazy instantiation and convenience methods

Question

Assume you have a Singleton Constants class, instance of which you\'d like to use throughout your application.

In someClass, therefore we

Answer 1

Following @vinceburn I would use the following example for constants and a singleton for more complex structures.

// Constants.h
// Replace PSMyApp for something more useful. e.g. company/name initials followed by app/class

// String example
NSString * const PSMyAppString = @"constantString"; 

// Logically related integers
typedef enum {
   PSMyAppRelatedValuesOne = 0,
   PSMyAppRelatedValuesTwo,
   PSMyAppRelatedValuesThree
} PSMyAppRelatedValues;

// Float example
const CGFloat PSMyAppFloat = 0.3f;

// Integer that has no related values
const NSInteger PSMyAppInteger = 2;

I prefer this over #define as I get auto completion and compiler checking and it fits more naturally with the way Apple does thing in some of the UIKit classes.