Added more detailed documentation regarding the class_instance object

lib/class.js

@@ -39,10 +39,23 @@ var class_meta = {};
 /**
  * Stores class instance visibility object
  *
- * For each instance id, an object exists that contains the private and
+ * An entry in this table exists for each instance, with the instance id (iid)
- * protected members.
+ * as the key. For each instance, there is always a base. The base will contain
+ * a proxy to the public members on the instance itself. The base will also
+ * contain all protected members.
  *
- * @type {Object.<number, Object>}
+ * Atop the base object is a private member object, with the base as its
+ * prototype. There exists a private member object for the instance itself and
+ * one for each supertype. This is stored by the class id (cid) as the key. This
+ * permits the private member object associated with the class of the method
+ * call to be bound to that method. For example, if a parent method is called,
+ * that call must be invoked in the context of the parent, so the private
+ * members of the parent must be made available.
+ *
+ * The resulting structure looks something like this:
+ *   class_instance = { iid: { cid: {} } }
+ *
+ * @type {Object.<number, Object<number, Object>>}
  */
 var class_instance = {};