Ember.js micro app alerts

# Make all controllers have a reference to the alerts controller.
# Kudos 1 - `needs` is a `concatenatedProperty`, so that specifying it further
#           in the iheritance chain it gets added up

Ember.ControllerMixin.reopen(                   
  needs: ['alerts']                             
  alert: (message, type) ->                     
    @get('controllers.alerts').pushObject(      
      type: type || 'success'                   
      message: message                          
    )                                           
)                                               

# Kudos 2 - debounce makes sure each message gets 1 second of show time, and it's a one-liner
App.AlertsController = Ember.ArrayController.extend(
  content: []
  contentObserver: ( ->
    Ember.run.debounce @, @shiftObject, 1000
  ).observes('content.@each')
)

# How to use
App.PostsController = Ember.ArrayController.extend(
  actions:
    buttonPush: () ->
      @alert('shithead')
)

# Template here: `alerts.hbs`
{{#each}}                  
  <p>{{message}}</p>       
{{else}}                   
  <p>No alerts</p>         
{{/each}}