#ifndef BOOST_MPL_VECTOR_AUX_ITEM_HPP_INCLUDED

#define BOOST_MPL_VECTOR_AUX_ITEM_HPP_INCLUDED

// Copyright Aleksey Gurtovoy 2000-2004

//

// Distributed under the Boost Software License, Version 1.0. 

// (See accompanying file LICENSE_1_0.txt or copy at 

// http://www.boost.org/LICENSE_1_0.txt)

//

// See http://www.boost.org/libs/mpl for documentation.

// $Source: /cvsroot/boost/boost/boost/mpl/vector/aux_/item.hpp,v $

// $Date: 2005/05/15 00:39:04 $

// $Revision: 1.8 $

#include <boost/mpl/long.hpp>

#include <boost/mpl/void.hpp>

#include <boost/mpl/next_prior.hpp>

#include <boost/mpl/aux_/type_wrapper.hpp>

#include <boost/mpl/aux_/config/typeof.hpp>

#include <boost/mpl/aux_/config/ctps.hpp>

namespace boost { namespace mpl {

#if defined(BOOST_MPL_CFG_TYPEOF_BASED_SEQUENCES)

template< 

      typename T

    , typename Base

    , int at_front = 0

    >

struct v_item

    : Base

{

    typedef typename Base::upper_bound_ index_;

    typedef typename next<index_>::type upper_bound_;

    typedef typename next<typename Base::size>::type size;

    typedef Base base;

    typedef v_item type;

    // agurt 10/sep/04: MWCW <= 9.3 workaround here and below; the compiler

    // breaks if using declaration comes _before_ the new overload

    static aux::type_wrapper<T> item_(index_);

    using Base::item_;

};

template<

      typename T

    , typename Base

    >

struct v_item<T,Base,1>

    : Base

{

    typedef typename prior<typename Base::lower_bound_>::type index_;

    typedef index_ lower_bound_;

    typedef typename next<typename Base::size>::type size;

    typedef Base base;

    typedef v_item type;

    static aux::type_wrapper<T> item_(index_);

    using Base::item_;

};

// "erasure" item

template< 

      typename Base

    , int at_front

    >

struct v_mask

    : Base

{

    typedef typename prior<typename Base::upper_bound_>::type index_;

    typedef index_ upper_bound_;

    typedef typename prior<typename Base::size>::type size;

    typedef Base base;

    typedef v_mask type;

    static aux::type_wrapper<void_> item_(index_);

    using Base::item_;

};

template< 

      typename Base

    >

struct v_mask<Base,1>

    : Base

{

    typedef typename Base::lower_bound_ index_;

    typedef typename next<index_>::type lower_bound_;

    typedef typename prior<typename Base::size>::type size;

    typedef Base base;

    typedef v_mask type;

    static aux::type_wrapper<void_> item_(index_);

    using Base::item_;

};

#endif // BOOST_MPL_CFG_TYPEOF_BASED_SEQUENCES

}}

#endif // BOOST_MPL_VECTOR_AUX_ITEM_HPP_INCLUDED