ceph/src/boost/boost/numeric/conversion/detail/udt_builtin_mixture.hpp

   1 //  (c) Copyright Fernando Luis Cacciola Carballal 2000-2004
   2 //  Use, modification, and distribution is subject to the Boost Software
   3 //  License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   4 //  http://www.boost.org/LICENSE_1_0.txt)
   5
   6 //  See library home page at http://www.boost.org/libs/numeric/conversion
   7 //
   8 // Contact the author at: fernando_cacciola@hotmail.com
   9 //
  10 #ifndef BOOST_NUMERIC_CONVERSION_DETAIL_UDT_BUILTIN_MIXTURE_FLC_12NOV2002_HPP
  11 #define BOOST_NUMERIC_CONVERSION_DETAIL_UDT_BUILTIN_MIXTURE_FLC_12NOV2002_HPP
  12
  13 #include "boost/type_traits/is_arithmetic.hpp"
  14
  15 #include "boost/numeric/conversion/udt_builtin_mixture_enum.hpp"
  16 #include "boost/numeric/conversion/detail/meta.hpp"
  17
  18 #include "boost/mpl/integral_c.hpp"
  19
  20 namespace boost { namespace numeric { namespace convdetail
  21 {
  22   // Integral Constants for 'UdtMixture'
  23   typedef mpl::integral_c<udt_builtin_mixture_enum, builtin_to_builtin> builtin2builtin_c ;
  24   typedef mpl::integral_c<udt_builtin_mixture_enum, builtin_to_udt>     builtin2udt_c ;
  25   typedef mpl::integral_c<udt_builtin_mixture_enum, udt_to_builtin>     udt2builtin_c ;
  26   typedef mpl::integral_c<udt_builtin_mixture_enum, udt_to_udt>         udt2udt_c ;
  27
  28   // Metafunction:
  29   //
  30   //   for_udt_mixture<UdtMixture,BuiltIn2BuiltIn,BuiltIn2Udt,Udt2BuiltIn,Udt2Udt>::type
  31   //
  32   // {UdtMixture} is one of the Integral Constants for UdMixture, declared above.
  33   // {BuiltIn2BuiltIn,BuiltIn2Udt,Udt2BuiltIn,Udt2Udt} are aribtrary types. (not metafunctions)
  34   //
  35   // According to the value of 'UdtMixture', selects the corresponding type.
  36   //
  37   template<class UdtMixture, class BuiltIn2BuiltIn, class BuiltIn2Udt, class Udt2BuiltIn, class Udt2Udt>
  38   struct for_udt_builtin_mixture
  39   {
  40     typedef typename
  41       ct_switch4<UdtMixture
  42                  , builtin2builtin_c, builtin2udt_c, udt2builtin_c // default
  43                  , BuiltIn2BuiltIn  , BuiltIn2Udt  , Udt2BuiltIn  , Udt2Udt
  44                 >::type
  45         type ;
  46   } ;
  47
  48   // Metafunction:
  49   //
  50   //   get_udt_mixture<T,S>::type
  51   //
  52   // Selects the appropriate UdtMixture Integral Constant for the combination T,S.
  53   //
  54   template<class T,class S>
  55   struct get_udt_builtin_mixture
  56   {
  57     typedef is_arithmetic<S> S_builtin ;
  58     typedef is_arithmetic<T> T_builtin ;
  59
  60     typedef typename
  61       for_both<S_builtin, T_builtin, builtin2builtin_c, builtin2udt_c, udt2builtin_c, udt2udt_c>::type
  62         type ;
  63   } ;
  64
  65 } } } // namespace boost::numeric::convdetail
  66
  67 #endif
  68
  69