//-----------------------------------------------------------------------------
// boost fsm/state.hpp header file
// See http://www.boost.org for updates, documentation, and revision history.
//-----------------------------------------------------------------------------
//
// Copyright (c) 2002
// Aleksey Gurtovoy
//
// Permission to use, copy, modify, distribute and sell this software
// and its documentation for any purpose is hereby granted without fee, 
// provided that the above copyright notice appears in all copies and 
// that both the copyright notice and this permission notice appear in 
// supporting documentation. No representations are made about the 
// suitability of this software for any purpose. It is provided "as is" 
// without express or implied warranty.

#ifndef BOOST_FSM_STATE_INCLUDED
#define BOOST_FSM_STATE_INCLUDED

#include "boost/mpl/integral_c.hpp"

namespace fsm {
namespace aux {

namespace mpl = boost::mpl;

// represent a FSM state

template<
      typename T
    , long State
    , void (T::* invariant_func)() const
    >
struct state
    : mpl::integral_c<long,State>
{
    static long do_check_invariant(T const& x)
    {
        if (invariant_func) (x.*invariant_func)();
        return State;
    }
};

} // namespace aux
} // namespace fsm

#endif // BOOST_FSM_STATE_INCLUDED