xpcom/glue/unused.h

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   4 /* ***** BEGIN LICENSE BLOCK *****
   5  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   6  *
   7  * The contents of this file are subject to the Mozilla Public License Version
   8  * 1.1 (the "License"); you may not use this file except in compliance with
   9  * the License. You may obtain a copy of the License at:
  10  * http://www.mozilla.org/MPL/
  11  *
  12  * Software distributed under the License is distributed on an "AS IS" basis,
  13  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  14  * for the specific language governing rights and limitations under the
  15  * License.
  16  *
  17  * The Original Code is Mozilla Code.
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  19  * The Initial Developer of the Original Code is
  20  *   The Mozilla Foundation
  21  * Portions created by the Initial Developer are Copyright (C) 2010
  22  * the Initial Developer. All Rights Reserved.
  23  *
  24  * Contributor(s):
  25  *   Chris Jones <jones.chris.g@gmail.com>
  26  *
  27  * Alternatively, the contents of this file may be used under the terms of
  28  * either the GNU General Public License Version 2 or later (the "GPL"), or
  29  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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  39  * ***** END LICENSE BLOCK ***** */
  40
  41 #ifndef mozilla_unused_h
  42 #define mozilla_unused_h
  43
  44 #include "nscore.h"
  45
  46 namespace mozilla {
  47
  48 //
  49 // Suppress GCC warnings about unused return values with
  50 //   unused << SomeFuncDeclaredWarnUnusedReturnValue();
  51 //
  52 struct NS_COM_GLUE unused_t { };
  53
  54 extern const unused_t NS_COM_GLUE unused;
  55
  56 template<typename T>
  57 inline void operator<<(const unused_t& /*unused*/, const T& /*unused*/) { }
  58
  59 }
  60
  61 #endif // mozilla_unused_h