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// Copyright Aleksey Gurtovoy 2002-2004
//
// 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.
// $Source$
// $Date: 2004-09-02 11:41:37 -0400 (Thu, 02 Sep 2004) $
// $Revision: 24874 $
#include <boost/mpl/inherit_linearly.hpp>
#include <boost/mpl/int.hpp>
#include <boost/mpl/list.hpp>
#include <iostream>
namespace mpl = boost::mpl;
using namespace mpl::placeholders;
template< typename Base, typename T >
struct tuple_part
: Base
{
typedef tuple_part type; // note the typedef
typedef typename Base::index::next index;
friend T& field(tuple_part& t, index) { return t.field_; }
T field_;
};
struct empty_tuple
{
typedef mpl::int_<-1> index;
};
typedef mpl::inherit_linearly<
mpl::list<int,char const*,bool>
, tuple_part<_,_>
, empty_tuple
>::type my_tuple;
int main()
{
my_tuple t;
field(t, mpl::int_<0>()) = -1;
field(t, mpl::int_<1>()) = "text";
field(t, mpl::int_<2>()) = false;
std::cout
<< field(t, mpl::int_<0>()) << '\n'
<< field(t, mpl::int_<1>()) << '\n'
<< field(t, mpl::int_<2>()) << '\n'
;
return 0;
}
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