Objective-C Closure

gistfile1.m

// compiled with ARC enabled

NSArray *foo() {
    NSMutableArray *res = [NSMutableArray array];
    for (int i = 0; i < 3; i++) {
        [res addObject:^{
            NSLog(@"%d", i);
        }];
    }
    return res;
}

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        NSArray *funcs = foo();
        [funcs makeObjectsPerformSelector:@selector(invoke)];
    }
}

// prints:
// 0
// 1
// 2

It's handy that blocks implement -invoke :)