Does Objective-C forbid use of structs?

Question

I\'m new to Objective C

I tried using a simple struct and got

arc forbids objective-c objects in struct

Looking up ARC, it

Answer 1

You can use struct in Objective-C++ with ARC in any case.

#import 

@interface City : NSObject
struct Data {
    NSString *name;
};

@property struct Data data;
@end

@implementation City
@end

int main()
{
    City *city = [[City alloc] init];
    city.data = (struct Data){@"San Francisco"};
    NSLog(@"%@", city.data.name);
    return 0;
}

If you compile it as Objective-C, you failed as you said.

$ clang -x objective-c -fobjc-arc a.m -framework Foundation 
a.m:5:15: error: ARC forbids Objective-C objects in struct
    NSString *name;
              ^
1 error generated.

Because C struct doesn't have the capability of management for variable life span.

But in C++, struct does have destructor function. So C++ struct is compatible with ARC.

$ clang++ -x objective-c++ -fobjc-arc a.m -framework Foundation
$ ./a.out
San Francisco