Error using Ember.arrayComputed

arrayComputed.js

allRules: function() {
  var options = {
    initialize: function(array, changeMeta, instanceMeta) {
      console.log("initialize array: ", array);
      return array;
    },
    addedItem: function(array, item, changeMeta, instanceMeta) {
      console.log("addedItem - item: ", item);
      array.push(item);
      return array;
    },
    removedItem: function(array, item, changeMeta, instanceMeta) {
      console.log("removedItem - item: ", item);
      array.push(item);
      return array;
    }
  }
  return Ember.arrayComputed('rules', 'actionRules', options);
}.on('init'),

Do you have more context? is allRules meant to be the property? I think what you might want is:

allRules: Ember.arrayComputed('rules', 'actionRules', {
    initialize: function(array, changeMeta, instanceMeta) {
      console.log("initialize array: ", array);
      return array;
    },
    addedItem: function(array, item, changeMeta, instanceMeta) {
      console.log("addedItem - item: ", item);
      array.push(item);
      return array;
    },
    removedItem: function(array, item, changeMeta, instanceMeta) {
      console.log("removedItem - item: ", item);
      array.push(item);
      return array;
    }
  })