1@interface Foo(RightSub) <P2> 2@property id right_sub_prop; 3@end 4 5@interface Foo() { 6@public 7 int right_sub_ivar; 8} 9@end 10 11@protocol P4 12- (void)p4_method; 13@property (retain) id p4_prop; 14@end 15 16@interface Foo(LeftP4) <P4> 17@end 18