Objective-C looping through array using a block

loop.m

    NSArray *array = @[
                            @"hello",
                            @"world",
                            [NSNull null],
                            @123,
                            @123.456
                      ];

    [array enumerateObjectsUsingBlock:^(id obj, NSUInteger i, BOOL *stop) {
        NSLog(@"obj %d is %@", i, obj);
    }];