reduce redundant filter & without syntax

labs/dependency-examples/backbone_marionette_require/js/collections/TodoList.js

@@ -7,21 +7,17 @@ define([
 ], function (Backbone, Todo) {
 	'use strict';
 
-	function isCompleted(todo) {
-		return todo.get('completed');
-	}
-
 	return Backbone.Collection.extend({
 		model: Todo,
 
 		localStorage: new Backbone.LocalStorage('todos-backbone'),
 
 		getCompleted: function () {
-			return this.filter(isCompleted);
+			return this.where({completed:true});
 		},
 
 		getActive: function () {
-			return this.reject(isCompleted);
+			return this.where({completed:false});
 		},
 
 		comparator: function (todo) {