updated using stacks example

loiane · loiane · commit 23c8ea80d123 · 2016-01-22T21:16:36.000-02:00
diff --git a/chapter03/02-UsingStacks.html b/chapter03/02-UsingStacks.html
@@ -6,6 +6,8 @@
 </head>
 <body>
 <script type="text/javascript" src="01-Stack.js"></script>
+<script type="text/javascript" src="01-Stack2.js"></script>
+<script type="text/javascript" src="01-Stack3.js"></script>
 <script type="text/javascript" src="02-UsingStacks.js"></script>
 </body>
 </html>
diff --git a/chapter03/02-UsingStacks.js b/chapter03/02-UsingStacks.js
@@ -10,4 +10,15 @@ var stack = new Stack();
  stack.pop();
  stack.pop();
  console.log(stack.size()); // outputs 2
- stack.print(); // outputs [5, 8]
+ stack.print(); // outputs [5, 8]
+
+
+//how to ensure true privacy
+//in case using Stack 2 uncomment code below
+/*var objectSymbols = Object.getOwnPropertySymbols(stack);
+
+ console.log(objectSymbols.length); // 2
+ console.log(objectSymbols);        // [Symbol(a), Symbol(b)]
+ console.log(objectSymbols[0]);     // Symbol(a)
+ stack[objectSymbols[0]].push(1);
+ stack.print();*/
