/**
 * @file
 * $Id$
 * $Revision$
 * $Author$
 * $Date$
 *
 * This file is part of The iWear Framework.
 *
 * The iWear Framework 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 as in version 2 of the License.

 * 
 * The iWear Framework 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 General Public License for
 * more details.
 * 
 * You should have received a copy of the GNU General Public License along with
 * The iWear Framework; if not, write to the Free Software Foundation, Inc., 59
 * Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#ifndef __IWEAR_FUNCTOR_H
#define __IWEAR_FUNCTOR_H

#include "iwear/cstdint.h"

namespace iwear
{

template<class T, class R = void>
class Functor
{
public:
    virtual R operator()(const T&) = 0;
    virtual ~Functor() { }
};

template<class R>
class Functor<void,R>
{
public:
    virtual R operator()( void ) = 0;
    virtual ~Functor() { }
};

template<class T, class U, class R = void>
class DualFunctor
{
public:
    virtual R operator()(const T&, const U&) = 0;
    virtual ~DualFunctor() { }
};

template<class T, class U, class V, class R = void>
class TripleFunctor
{
public:
    virtual R operator()(const T&, const U&, const V&) = 0;
    virtual ~TripleFunctor() { }
};

typedef Functor<uint32_t> Uint32Functor;
typedef Functor<int32_t>  Int32Functor;
typedef Functor<double>   DoubleFunctor;
typedef Functor<void>	  VoidFunctor;

typedef DualFunctor<uint32_t,uint32_t> Uint32Uint32Functor;

}

#endif