weak
#ifndef weakify
#if __has_feature(objc_arc)
#define weakify(object) autoreleasepool{} __weak __typeof__(object) weak##_##object = object;
#else
#define weakify(object) autoreleasepool{} __block __typeof__(object) block##_##object = object;
#endif
#endif
#ifndef strongify
#if __has_feature(objc_arc)
#define strongify(object) try{} @finally{} __typeof__(object) strong##_##object = weak##_##object;
#else
#define strongify(object) try{} @finally{} __typeof__(object) strong##_##object = block##_##object;
#endif
#endif