How to sync JavaScript callbacks?

Question

I\'ve been developing in JavaScript for quite some time but net yet a cowboy developer, as one of the many things that always haunts me is synching JavaScript\'s callbacks.<

Answer 1

With this helper function:

function afterAll(callback,what) {
  what.counter = (what.counter || 0) + 1;
  return function() {
    callback(); 
    if(--what.counter == 0) 
      what();
  };
}

your loop will look like this:

function whenAllDone() { ... }
for (... in ...) {
  myFunc1(afterAll(callback,whenAllDone)); 
}

here afterAll creates proxy function for the callback, it also decrements the counter. And calls whenAllDone function when all callbacks are complete.