Alchemiq

Alchemiq was created to provide possibility of using mixins (aka traits) in Objective-C. Inspired by mixin ideas in Ruby modules and Swift protocol extensions. Different from https://github.com/vl4dimir/ObjectiveMixin in much more convenient API. Just like in Swift, you just need to make your class to conform some Mixin (Protocol actually), and all implementation for this mixin will be added to your class in runtime. What is convenient - after adopting some mixin, you can call any methods (class methods, instance methods, setters and getters) without any type casting.

Brilliant, huh?! ^^

Requirements

ios 8.0 or higher

How to start

1. First, you need to call method [AQAlchemiq addMixins] in your AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    [AQAlchemiq addMixins];
    return YES;
}

Doing this you start process of collecting all mixins, their descriptions and your classes you want to conform some mixin!

2. To create your own mixin, you have a protocol AQMixin and class AQMixinDescription

• Create your own mixin (actually protocol), which has to conform AQMixin protocol. You may add @required methods & properties as well as @optional (Alchemiq prevents any warnings in your class conforming mixin protocol).

@protocol SomeMixin <AQMixin>
//Add your methods or properties here
- (void)someMethod;
@end

• You can conform your mixin to any other protocols in addition to AQMixin. Only implemented methods from that protocols will be injected into your class.

@protocol SomeMixin <AQMixin, UITableViewDataSource, UITableViewDelegate>
//Add your methods or properties here
- (void)someMethod;
@end

• Then you have to add implementation for your mixin, which will be injected to your class. You can do it by creating own class, which inherits from AQMixinDescription and conforms to your created mixin.

@interface SomeMixinDescription <SomeMixin>
@end

@implementation SomeMixinDescription
- (void)someMethod {
    //Implementation
}
@end

• After that you can implement methods inside of your MixinDescription class.

3. Then just make your own whatever class to conform your mixin. Now you can call methods from mixin and be sure, that their implementation will be added during runtime.

@interface SomeViewController <SomeMixin>
@end

@implementation SomeViewController
- (void)viewDidLoad {
    [super viewDidLoad];
    [self someMethod];
}
@end

What is important:

1. Your mixin description class should have definite name like this "[mixin_protocol_name]Description". For example, if you have mixin called SomeMixin, then your mixin description should have name SomeMixinDescription
2. For generation of setters and getters, use @synthesize construction.

@protocol SomeMixin <AQMixin>

@property (strong, nonatomic) NSString someProperty;

@end

@interface SomeMixinDescription <SomeMixin>
@end

@implementation SomeMixinDescription

@synthesize someProperty;

@end

3. Only implemented methods will be injected into your class with mixin.
4. You can use setters and getters for properties, but iVars are not available now.

Example

To run the example project, clone the repo, and run pod install from the Example directory first.

Installation

Alchemiq is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod "Alchemiq"

Author

Aleksey Getman, getmanag@gmail.com

License

Alchemiq is available under the MIT license. See the LICENSE file for more info.