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: [email protected] 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 70