那么这两个版本之间的实际区别是什么:@interfaceFoo:NSObject//Aguywalksintoabar.@property(nonatomic,copy)NSString*bar;@end//Implementationfile@interfaceFoo()@property(nonatomic,retain)NSArray*baz;@end和@interfaceFoo:NSObject//Aguywalksintoabar.@public@property(nonatomic,copy)NSString*bar;@private@property(nonatomic,