simple-pub-sub.js

var extend = function(t, f){ for ( var p in f ) t[p] = f[p]; return t }

// a Pub/Sub mixin
var Hub = {
  sub: function(name, cb){
    if ( ! this.channels ) this.channels = {}
    if ( ! this.channels[name]) this.channels[name] = []
    this.channels[name].push(cb)
    return this
  },
  pub: function(name, msg){
    if ( ! this.channels || ! this.channels[name] ) return this
    this.channels[name].forEach(function(cb){ cb(msg) })
    return this
  }
}

// mix in Hub to some object, just because we can. that obj may have lots of other logic
var myHub = extend({}, Hub)

// our callback is just a sub to our pub
myHub.sub('my event', function(msg){ console.log('first subscriber to:', msg) })
myHub.sub('my event', function(msg){ console.log('second subscriber to:', msg) })
myHub.pub('my event', 'hi there')

var myHub2 = extend({}, Hub)

myHub2.pub('my event', 'wait, no one is listening')