c4arl0s/adoptingmodern-objectivec

AdoptingModern-ObjectiveC

AdoptingModern-ObjectiveC

AdoptingModern-ObjectiveC

instancetype

@interface MyObject : NSObject
+ (instancetype)factoryMethodA;
+ (id)factoryMethodB;
@end
 
@implementation MyObject
+ (instancetype)factoryMethodA { return [[[self class] alloc] init]; }
+ (id)factoryMethodB { return [[[self class] alloc] init]; }
@end
 
void doSomething() {
    NSUInteger x, y;
 
    x = [[MyObject factoryMethodA] count]; // Return type of +factoryMethodA is taken to be "MyObject *"
    y = [[MyObject factoryMethodB] count]; // Return type of +factoryMethodB is "id"
}

For example:

@interface MyObject
- (id)myFactoryMethod;
@end

should become:

@interface MyObject
- (instancetype)myFactoryMethod;
@end

Properties

Enumeration Macros

Object Initialization

Automatic Reference Counting (ARC)

Refactoring Your Code Using Xcode