Objective-C 宏，用于包装枚举定义 – 为枚举值生成内联函数以查找字符串/名称。
RAMEnum(Usefulness,
typedef NS_ENUM(NSUInteger, Usefulness) {
kUsefulnessUseful,
kUsefulnessVeryUseful ,
kUsefulnessSuperUseful,
kUsefulnessUseless
}
);
...
...
Usefulness someUsefulness = kUsefulnessVeryUseful;
NSLog(@"Usefulness: %@", UsefulnessName(someUsefulness)); //"Usefulness: kUsefulnessVeryUseful"