/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"

%{C++
#define NS_ENUMERATOR_FALSE 1
%}
/*
 * DO NOT USE THIS INTERFACE.  IT IS HORRIBLY BROKEN, USES NS_COMFALSE
 * AND IS BASICALLY IMPOSSIBLE TO USE CORRECTLY THROUGH PROXIES OR
 * XPCONNECT.  IF YOU SEE NEW USES OF THIS INTERFACE IN CODE YOU ARE
 * REVIEWING, YOU SHOULD INSIST ON nsISimpleEnumerator.
 *
 * DON'T MAKE ME COME OVER THERE.
 */
[scriptable, uuid(ad385286-cbc4-11d2-8cca-0060b0fc14a3)]
interface nsIEnumerator : nsISupports {
  /** First will reset the list. will return NS_FAILED if no items
   */
  void first();

  /** Next will advance the list. will return failed if already at end
   */
  void next();

  /** CurrentItem will return the CurrentItem item it will fail if the 
   *  list is empty
   */
  nsISupports currentItem();

  /** return if the collection is at the end.  that is the beginning following 
   *  a call to Prev and it is the end of the list following a call to next
   */
  void isDone();
};

[uuid(75f158a0-cadd-11d2-8cca-0060b0fc14a3)]
interface nsIBidirectionalEnumerator : nsIEnumerator {

  /** Last will reset the list to the end. will return NS_FAILED if no items
   */
  void last();

  /** Prev will decrement the list. will return failed if already at beginning
   */
  void prev();
};