pubsub.js

;(function (root) {
 'use strict';

 function PubSub () {
    this.topics = {};
 }

 PubSub.prototype.subscribe = function (name, fn) {
    this.topics[name] = this.topics[name] || [];
    this.topics[name].push(fn);
 };

 PubSub.prototype.publish = function(name, args) {
    this.topics[name] = this.topics[name] || [];
    this.topics[name].forEach(function(fn) {
      fn.apply(this, args);
    });
 };

 root.PubSub = new PubSub();

} (window));

PubSub.subscribe('foo', function (a, b) {
  console.log('foo callback', a, b)
});

PubSub.subscribe('foo', function (a, b) {
  console.log('hey there, thats foo callback ', a, b)
});

PubSub.publish('foo', ['arg A', 'arg b']); // log: foo callback "myargument A" "arg b"