MySources/boost_graph/boost/numeric/conversion/detail/conversion_traits.hpp

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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_CONVERSION_TRAITS_FLC_12NOV2002_HPP
#define BOOST_NUMERIC_CONVERSION_DETAIL_CONVERSION_TRAITS_FLC_12NOV2002_HPP
#include "boost/type_traits/is_arithmetic.hpp"
#include "boost/type_traits/is_same.hpp"
#include "boost/type_traits/remove_cv.hpp"
#include "boost/numeric/conversion/detail/meta.hpp"
#include "boost/numeric/conversion/detail/int_float_mixture.hpp"
#include "boost/numeric/conversion/detail/sign_mixture.hpp"
#include "boost/numeric/conversion/detail/udt_builtin_mixture.hpp"
#include "boost/numeric/conversion/detail/is_subranged.hpp"
namespace boost { namespace numeric { namespace convdetail
{
//-------------------------------------------------------------------
// Implementation of the Conversion Traits for T != S
//
// This is a VISIBLE base class of the user-level conversion_traits<> class.
//-------------------------------------------------------------------
template<class T,class S>
struct non_trivial_traits_impl
{
typedef typename get_int_float_mixture <T,S>::type int_float_mixture ;
typedef typename get_sign_mixture <T,S>::type sign_mixture ;
typedef typename get_udt_builtin_mixture <T,S>::type udt_builtin_mixture ;
typedef typename get_is_subranged<T,S>::type subranged ;
typedef mpl::false_ trivial ;
typedef T target_type ;
typedef S source_type ;
typedef T result_type ;
typedef typename mpl::if_< is_arithmetic<S>, S, S const&>::type argument_type ;
typedef typename mpl::if_<subranged,S,T>::type supertype ;
typedef typename mpl::if_<subranged,T,S>::type subtype ;
} ;
//-------------------------------------------------------------------
// Implementation of the Conversion Traits for T == S
//
// This is a VISIBLE base class of the user-level conversion_traits<> class.
//-------------------------------------------------------------------
template<class N>
struct trivial_traits_impl
{
typedef typename get_int_float_mixture <N,N>::type int_float_mixture ;
typedef typename get_sign_mixture <N,N>::type sign_mixture ;
typedef typename get_udt_builtin_mixture<N,N>::type udt_builtin_mixture ;
typedef mpl::false_ subranged ;
typedef mpl::true_ trivial ;
typedef N target_type ;
typedef N source_type ;
typedef N const& result_type ;
typedef N const& argument_type ;
typedef N supertype ;
typedef N subtype ;
} ;
//-------------------------------------------------------------------
// Top level implementation selector.
//-------------------------------------------------------------------
template<class T, class S>
struct get_conversion_traits
{
typedef typename remove_cv<T>::type target_type ;
typedef typename remove_cv<S>::type source_type ;
typedef typename is_same<target_type,source_type>::type is_trivial ;
typedef trivial_traits_impl <target_type> trivial_imp ;
typedef non_trivial_traits_impl<target_type,source_type> non_trivial_imp ;
typedef typename mpl::if_<is_trivial,trivial_imp,non_trivial_imp>::type type ;
} ;
} } } // namespace boost::numeric::convdetail
#endif