Dirty Promise Pattern

gistfile1.txt

var Promise = function(inst) {
	if (inst instanceof Promise) {
		return inst;
	}
	else {
		this.promises = [];	
		return this;
	}
	

};
Promise.prototype.execute = function(fn) {
	this.promises.push(fn);
	this.resolve();
	return this;
};
Promise.prototype.resolve = function(first_argument) {
	// body...
	if(this.promises.length  === 0) {
		this.done();
	}
	this.promises.shift().call();
};
Promise.prototype.then = function(fn) {
	this.promises.push(fn);
	return this;
};

Promise.prototype.done = function(fn) {
	fn.call();
};


/*
* Three function to simulate Async nature.. 
*/
function a() {
	var pro = new Promise(promiseInst)
	setTimeout(function() {
		console.log('excecutin A');
		pro.resolve();
	},2000);

}

function b() {
	var pro = new Promise(promiseInst)
	setTimeout(function() {
		console.log('excecutin B');
		pro.resolve();
	},2000);

};

function c() {
	var pro = new Promise(promiseInst);
	setTimeout(function() {
		console.log('excecutin C');
		pro.resolve();
	},2000);

};


//Lets test it out..

var promiseInst = new Promise();
promiseInst.execute(a)
	.then(b)
	.then(c)
	.then(function() {
	console.log('WE ARE DONE');
});