为 Objective-C 写了框架，虽然已经 49 年了！

为 Objective-C 的 Protocol 增加扩展，达到 Objective-C 的 POP 编程效果。

/// 声明协议

@protocol NNCodeProtocol <NSObject>

@optional
+ (void)sayHelloPop;
- (void)sayHelloPop;

@end

@protocol NNCodeWhoProtocol <NNCodeProtocol>

@optional
@property (nonatomic, strong) NSString* who;

@end

/// 对 NNCodeWhoProtocol 协议实现扩展

@nn_extension(NNCodeWhoProtocol, @nn_where(self == [NNCodeObjc class]), NNCodeNameProtocol)

+ (void)sayHelloPop {
    DLog(@"+[%@ %s] objc says hello pop", self, sel_getName(_cmd));
}

- (void)sayHelloPop {
    DLog(@"-[%@ %s] objc says hello pop", [self class], sel_getName(_cmd));
}

- (NSString *)who {
    NSString *who = [NSString stringWithFormat:@"-[%@ %s] objc says I am %@", [self class], sel_getName(_cmd), self.name];
    return who;
}

- (void)setWho:(NSString *)who {
	@nn_exscope(self) {
		@nn_inscope(NNCodeObjc *, self)
		self.name = who;
	}
}

@end

///声明 NNCodeObjc 类，并遵守 NNCodeWhoProtocol 协议，获取 NNCodeWhoProtocol 协议扩展实现方法

@protocol NNCodeNameProtocol <NSObject>

@optional
@property (nonatomic, strong) NSString* name;

@end

@interface NNCodeObjc : NSObject <NNCodeWhoProtocol, NNCodeNameProtocol>

@property (nonatomic, strong) NSString *name;

@end

@implementation NNCodeObjc

@end

///调用

[NNCodeObjc sayHelloPop];

NNCodeObjc *objc = [NNCodeObjc new];
[objc sayHelloPop];

objc.who = @"objc";
DLog(@"%@", objc.who);

项目地址：

• NNPopObjc

类似项目：

• libextobjc
• ProtocolKit