Simple pubsub implementation in coffee

pubsub.coffee

window.ActiveAdminSortableEvent = do ->
  eventToListeners = {}

  return {
    add: (event, callback) ->
      if not eventToListeners.hasOwnProperty(event)
        eventToListeners[event] = []
      eventToListeners[event].push(callback)

    trigger: (event, args) ->
      if eventToListeners.hasOwnProperty(event)
        for callback in eventToListeners[event]
          try
            callback.call(null, args)
          catch e
            console.error(e) if console and console.error
  }

ActiveAdminSortableEvent.add 'ajaxDone', ->
  alert('Done')

ActiveAdminSortableEvent.trigger('ajaxDone')