Add events to regular js objects using coffeescript. .on, .off, and event chaining with bailout when callback returns false.

eventable.coffee

class app.Eventable

  callbackRegistry = {}

  @off: (event, callback) ->
    callbacks = callbackRegistry[event]
    callbackRegistry[event] = _.without(callbacks, callback)

  @on: (event, callback) ->
    if typeof callback == "function"
      callbackRegistry[event] ||= []
      callbackRegistry[event].push callback
    else
      throw new Error "callbacks must be functions"

  @trigger: (event, payload) =>
    console.log "event: #{event}! with : #{payload}"
    @_runCallbacks event

  @_runCallbacks: (event) =>
    callbacks = callbackRegistry[event] || []
    for callback in callbacks
      if callback() == false
        break