Question

In my ongoing saga to understand more about Object Oriented Javascript – I came across a question about creating a class to respond to the following API:

var foo = new bar().delay(750).start().then(onComplete);

var bar = function() {
    this.delay(function(per) {
      //...
    };
}

Can someone with more experience than me please describe how to create class that would respond to this? I have never seen chaining like this and can’t find any information online 🙁

Answer 1

This chaining is accomplished by returning this in your functions :

this.delay = function(per) {
  //...
  return this;
};

If you want to stick to first line code, then your constructor should be named bar :

var bar = function() {
    this.delay = function(per) {
      //...
      return this;
    };
    this.start = function() {
      ...
      return this;
    };
}

See demonstration (open the console)