File indexing completed on 2024-04-28 03:40:46

 /*
    Copyright 2007-2008 David Nolden <david.nolden.kdevelop@art-master.de>
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License version 2 as published by the Free Software Foundation.
 
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
 
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
 */
 
 #ifndef PUSHVALUE_H
 #define PUSHVALUE_H
 
 /**
  * A simple helper-class that does the following:
  * Backup the given reference-value given through @param ptr,
  * replace it with the value given through @param push,
  * restore the backed up value back on destruction.
  * */
 template<class Value>
 class PushValue {
   public:
     PushValue( Value& ptr, const Value& push = Value()  ) : m_ptr(ptr)  {
       m_oldPtr = m_ptr;
       m_ptr = push;
     }
     ~PushValue() {
       m_ptr = m_oldPtr;
     }
   private:
     Value& m_ptr;
     Value m_oldPtr;
 };
 
 ///Only difference to PushValue: The value is only replaced if the new value is positive
 template<class Value>
 class PushPositiveValue {
   public:
     PushPositiveValue( Value& ptr, const Value& push = Value()  ) : m_ptr(ptr)  {
       m_oldPtr = m_ptr;
       if( push ) {
         m_ptr = push;
       }
     }
     ~PushPositiveValue() {
       m_ptr = m_oldPtr;
     }
   private:
     Value& m_ptr;
     Value m_oldPtr;
 };
 
 #endif