How to call the same JavaScript function repeatedly while waiting for the function to run its course before invoking it again, using method chaining?

Question

Using method chaining, I am looking to fire a function repeatedly but only after the function has completed. Almost like don\'t execute until the function has fully run its

Answer 1

You are looking for Promises, though not supported across the board yet, you can use babel or traceur (or even jQuery's deferred) to use them now:

var myfunc = {
  copy: function(message) {
    return new Promise(function(resolve, reject) {
      setTimeout(function() {
        resolve(message);
      }, 1000);
    });
  }
}

// sequential processing
myfunc.copy('hello').then(function(message1) {
  console.log(message1);
  myfunc.copy('world').then(function(message2) {
    console.log(message2);
  });
});

// batch processing
Promise.all([myfunc.copy('hello'), myfunc.copy('world')]).then(function(values) {
  console.log(values.join(' '));
});

Reference: Promise, Promise.all, Promise.then