Question

dispatch_queue_t queue = dispatch_queue_create("setup_cell", NULL);

dispatch_async(queue, ^{
    //Line 1
    //Line 2
});

Would this wait until line 1 was finished, before calling line 2?

Answer 1

Yes (in most situations). Objective-C, like C is a top-down language, meaning that generally, a block code that happens above another block of code will execute before it.

The only real way this wouldn’t happen is through compiler optimization, but I wouldn’t worry about it, as compilers are usually smart enough to keep the code top-down even through all the optimizations they do.