Angular.js jQuery pubsub service

a_pubsub.js

angular.module('app').factory('pubsub', function() {
  var o = $({});
  
  $.subscribe = function() {
    o.on.apply(o, arguments);
  };
  
  $.unsubscribe = function() {
    o.off.apply(o, arguments);
  };
  
  $.publish = function() {
    o.trigger.apply(o, arguments);
  };
  
  return $;
});

controller.js

angular.module('app').controller('GrowlCtrl', ['$scope', 'pubsub', function ($scope, pubsub) {
  'use strict';

  $scope.notifications = [];

  pubsub.subscribe('growl', function (event, messageType, message) {
    $scope.notifications.push({
      type: messageType || '',
      msg: message
    });
  });

  $scope.close = function (index) {
    $scope.notifications.splice(index, 1);
  };
}]);

othercontroller.js

angular.module('app').controller('UsageCtrl', ['$scope', 'pubsub', function ($scope, pubsub) {
  'use strict';
  
  $scope.click = function () {
    pubsub.publish('growl', ['success', 'This is a success!']);
  };

}]);