1#define NS_DESIGNATED_INITIALIZER __attribute__((objc_designated_initializer)) 2 3@class NSString; 4 5@interface B1 6-(id)init; 7@end 8 9@interface S1 : B1 10-(int)prop; 11-(void)setProp:(int)p; 12+(id)s1; 13-(id)initWithFoo:(NSString*)foo; 14@end 15