qgsoptional.h

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/***************************************************************************
  qgsoptional.h - QgsOptional

 ---------------------
 begin                : 7.9.2016
 copyright            : (C) 2016 by Matthias Kuhn
 email                : [email protected]
 ***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
#ifndef QGSOPTIONAL_H
#define QGSOPTIONAL_H


template<class T>
class CORE_EXPORT QgsOptional
{
  public:
    QgsOptional()
        : mEnabled( false )
    {
    }

    QgsOptional( const T& data )
        : mEnabled( true )
        , mData( data )
    {
    }

    QgsOptional( const T& data, bool enabled )
        : mEnabled( enabled )
        , mData( data )
    {
    }

    bool operator== ( const QgsOptional<T>& other ) const
    {
      return mEnabled == other.mEnabled && mData == other.mData;
    }

    operator bool() const
    {
      return mEnabled;
    }

    bool enabled() const
    {
      return mEnabled;
    }

    void setEnabled( bool enabled )
    {
      mEnabled = enabled;
    }

    const T* operator->() const
    {
      return &mData;
    }

    T data() const
    {
      return mData;
    }

    void setData( const T& data )
    {
      mData = data;
    }

  private:
    bool mEnabled;
    T mData;
};

#endif // QGSOPTIONAL_H