#import int main() { @autoreleasepool { // NSArrays NSArray *immutable_array = @[ @"foo", @"bar" ]; NSMutableArray *mutable_array = [NSMutableArray arrayWithCapacity:2]; [mutable_array addObjectsFromArray:immutable_array]; // NSDictionaries NSDictionary *immutable_dictionary = @{ @"key" : @"value" }; NSMutableDictionary *mutable_dictionary = [NSMutableDictionary dictionaryWithCapacity:1]; [mutable_dictionary addEntriesFromDictionary:immutable_dictionary]; NSNumber *one = @1; NSLog(@"Stop here"); // Set breakpoint 0 here. } }