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// (c) Copyright Fernando Luis Cacciola Carballal 2000-2004
// Use, modification, and distribution is subject to 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 library home page at http://www.boost.org/libs/numeric/conversion
//
// Contact the author at: fernando_cacciola@hotmail.com
//
#ifndef BOOST_NUMERIC_CONVERSION_DETAIL_SIGN_MIXTURE_FLC_12NOV2002_HPP
#define BOOST_NUMERIC_CONVERSION_DETAIL_SIGN_MIXTURE_FLC_12NOV2002_HPP
#include "boost/config.hpp"
#include "boost/limits.hpp"
#include "boost/numeric/conversion/sign_mixture_enum.hpp"
#include "boost/numeric/conversion/detail/meta.hpp"
#include "boost/mpl/integral_c.hpp"
namespace boost { namespace numeric { namespace convdetail
{
// Integral Constants for 'SignMixture'
typedef mpl::integral_c<sign_mixture_enum, unsigned_to_unsigned> unsig2unsig_c ;
typedef mpl::integral_c<sign_mixture_enum, signed_to_signed> sig2sig_c ;
typedef mpl::integral_c<sign_mixture_enum, signed_to_unsigned> sig2unsig_c ;
typedef mpl::integral_c<sign_mixture_enum, unsigned_to_signed> unsig2sig_c ;
// Metafunction:
//
// get_sign_mixture<T,S>::type
//
// Selects the appropriate SignMixture Integral Constant for the combination T,S.
//
template<class T,class S>
struct get_sign_mixture
{
typedef mpl::bool_< ::std::numeric_limits<S>::is_signed > S_signed ;
typedef mpl::bool_< ::std::numeric_limits<T>::is_signed > T_signed ;
typedef typename
for_both<S_signed, T_signed, sig2sig_c, sig2unsig_c, unsig2sig_c, unsig2unsig_c>::type
type ;
} ;
// Metafunction:
//
// for_sign_mixture<SignMixture,Sig2Sig,Sig2Unsig,Unsig2Sig,Unsig2Unsig>::type
//
// {SignMixture} is one of the Integral Constants for SignMixture, declared above.
// {Sig2Sig,Sig2Unsig,Unsig2Sig,Unsig2Unsig} are aribtrary types. (not metafunctions)
//
// According to the value of 'SignMixture', selects the corresponding type.
//
template<class SignMixture, class Sig2Sig, class Sig2Unsig, class Unsig2Sig, class Unsig2Unsig>
struct for_sign_mixture
{
typedef typename
ct_switch4<SignMixture
, sig2sig_c, sig2unsig_c, unsig2sig_c // default
, Sig2Sig , Sig2Unsig , Unsig2Sig , Unsig2Unsig
>::type
type ;
} ;
} } } // namespace boost::numeric::convdetail
#endif
//
///////////////////////////////////////////////////////////////////////////////////////////////