mirror of
https://github.com/boostorg/mpl.git
synced 2025-10-04 11:41:00 +02:00
69 lines
2.2 KiB
C++
69 lines
2.2 KiB
C++
//-----------------------------------------------------------------------------
|
|
// boost mpl/example/integer.cpp source file
|
|
// See http://www.boost.org for updates, documentation, and revision history.
|
|
//-----------------------------------------------------------------------------
|
|
//
|
|
// Copyright (c) 2001-02
|
|
// 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.
|
|
|
|
#include "boost/mpl/arithmetic/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_c.hpp"
|
|
#include "boost/mpl/identity.hpp"
|
|
#include "boost/mpl/base.hpp"
|
|
#include "boost/mpl/apply_if.hpp"
|
|
#include "boost/mpl/apply.hpp"
|
|
#include "boost/mpl/begin_end.hpp"
|
|
#include "boost/mpl/assert_is_same.hpp"
|
|
|
|
namespace mpl = boost::mpl;
|
|
using namespace mpl::placeholder;
|
|
|
|
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_c<8> >
|
|
>
|
|
, mpl::int_c<bit_size>
|
|
>::type >::type iter_;
|
|
|
|
typedef typename mpl::end<builtins_>::type last_;
|
|
typedef typename mpl::apply_if<
|
|
boost::is_same<iter_,last_>
|
|
, mpl::identity< big_int<bit_size> >
|
|
, mpl::apply0<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_IS_SAME(int1, char);
|
|
BOOST_MPL_ASSERT_IS_SAME(int5, char);
|
|
BOOST_MPL_ASSERT_IS_SAME(int15, short);
|
|
BOOST_MPL_ASSERT_IS_SAME(int32, int);
|
|
BOOST_MPL_ASSERT_IS_SAME(int100, big_int<100>);
|