# window.onTrue = (object, path, callback) ->
#   if object.get(path)
#     callback()
#   else
#     observer = ->
#       object.removeObserver path, observer
#       callback()
#     object.addObserver path, observer
#
# window.onceLoaded = ->
#   objects = Array.prototype.slice.apply(arguments)
#   callback = objects.pop()
#
#   # sadly Ember.Enumerable.compact does not remove undefined values
#   objects = ((object || null) for object in objects).compact()
#   object = objects.shift()
#
#   if object
#     path = if Ember.isArray(object) then 'firstObject.isLoaded' else 'isLoaded'
#     onTrue object, path, ->
#       if objects.length == 0
#         callback(object)
#       else
#         onceLoaded.apply(objects + [callback])
#   else
#     callback object