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// Copyright Aleksey Gurtovoy 2001-2004
//
// 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.
// $Id$
// $Date$
// $Revision$
#include <boost/mpl/multiplies.hpp>
#include <boost/mpl/list.hpp>
#include <boost/mpl/lower_bound.hpp>
#include <boost/mpl/transform_view.hpp>
#include <boost/mpl/sizeof.hpp>
#include <boost/mpl/int.hpp>
#include <boost/mpl/identity.hpp>
#include <boost/mpl/base.hpp>
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/deref.hpp>
#include <boost/mpl/begin_end.hpp>
#include <boost/mpl/assert.hpp>
#include <boost/type_traits/is_same.hpp>
namespace mpl = boost::mpl;
using namespace mpl::placeholders;
template< int bit_size >
class big_int
{
// ...
};
template< int bit_size >
struct integer
{
typedef mpl::list<char,short,int,long> builtins_;
typedef typename mpl::base< typename mpl::lower_bound<
mpl::transform_view< builtins_
, mpl::multiplies< mpl::sizeof_<_1>, mpl::int_<8> >
>
, mpl::int_<bit_size>
>::type >::type iter_;
typedef typename mpl::end<builtins_>::type last_;
typedef typename mpl::eval_if<
boost::is_same<iter_,last_>
, mpl::identity< big_int<bit_size> >
, mpl::deref<iter_>
>::type type;
};
typedef integer<1>::type int1;
typedef integer<5>::type int5;
typedef integer<15>::type int15;
typedef integer<32>::type int32;
typedef integer<100>::type int100;
BOOST_MPL_ASSERT(( boost::is_same< int1, char > ));
BOOST_MPL_ASSERT(( boost::is_same< int5, char > ));
BOOST_MPL_ASSERT(( boost::is_same< int15, short > ));
BOOST_MPL_ASSERT(( boost::is_same< int32, int > ));
BOOST_MPL_ASSERT(( boost::is_same< int100, big_int<100> > ));
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