ObjectiveC wrapping C++

main.mm

#import <Foundation/Foundation.h>
#include <map>
#include <string>

struct CppType {
  std::map<std::string, std::string> myMap;
};

@interface ObjCType : NSObject {
  CppType map;
}
@end

@implementation ObjCType
@end

int main(int argc, const char * argv[]) {
  @autoreleasepool {
    NSLog(@"%s", @encode(ObjCType));
  }
  return 0;
}