xpcom/glue/nsArrayUtils.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is XPCOM Array implementation.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corp.
  19  * Portions created by the Initial Developer are Copyright (C) 2002
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Alec Flett <alecf@netscape.com>
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either the GNU General Public License Version 2 or later (the "GPL"), or
  27  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28  * in which case the provisions of the GPL or the LGPL are applicable instead
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  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #ifndef nsArrayUtils_h__
  40 #define nsArrayUtils_h__
  41
  42 #include "nsCOMPtr.h"
  43 #include "nsIArray.h"
  44
  45 // helper class for do_QueryElementAt
  46 class NS_COM_GLUE nsQueryArrayElementAt : public nsCOMPtr_helper
  47   {
  48     public:
  49       nsQueryArrayElementAt(nsIArray* aArray, PRUint32 aIndex,
  50                             nsresult* aErrorPtr)
  51           : mArray(aArray),
  52             mIndex(aIndex),
  53             mErrorPtr(aErrorPtr)
  54         {
  55           // nothing else to do here
  56         }
  57
  58       virtual nsresult NS_FASTCALL operator()(const nsIID& aIID, void**) const;
  59
  60     private:
  61       nsIArray*  mArray;
  62       PRUint32   mIndex;
  63       nsresult*  mErrorPtr;
  64   };
  65
  66 inline
  67 const nsQueryArrayElementAt
  68 do_QueryElementAt(nsIArray* aArray, PRUint32 aIndex, nsresult* aErrorPtr = 0)
  69   {
  70     return nsQueryArrayElementAt(aArray, aIndex, aErrorPtr);
  71   }
  72
  73 #endif // nsArrayUtils_h__