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_CONVERSION_TRAITS_FLC_12NOV2002_HPP
11 #define BOOST_NUMERIC_CONVERSION_DETAIL_CONVERSION_TRAITS_FLC_12NOV2002_HPP
12 
13 #include "boost/type_traits/is_arithmetic.hpp"
14 #include "boost/type_traits/is_same.hpp"
15 #include "boost/type_traits/remove_cv.hpp"
16 
17 #include "boost/numeric/conversion/detail/meta.hpp"
18 #include "boost/numeric/conversion/detail/int_float_mixture.hpp"
19 #include "boost/numeric/conversion/detail/sign_mixture.hpp"
20 #include "boost/numeric/conversion/detail/udt_builtin_mixture.hpp"
21 #include "boost/numeric/conversion/detail/is_subranged.hpp"
22 
23 namespace boost { namespace numeric { namespace convdetail
24 {
25   //-------------------------------------------------------------------
26   // Implementation of the Conversion Traits for T != S
27   //
28   // This is a VISIBLE base class of the user-level conversion_traits<> class.
29   //-------------------------------------------------------------------
30   template<class T,class S>
31   struct non_trivial_traits_impl
32   {
33     typedef typename get_int_float_mixture   <T,S>::type int_float_mixture ;
34     typedef typename get_sign_mixture        <T,S>::type sign_mixture ;
35     typedef typename get_udt_builtin_mixture <T,S>::type udt_builtin_mixture ;
36 
37     typedef typename get_is_subranged<T,S>::type subranged ;
38 
39     typedef mpl::false_ trivial ;
40 
41     typedef T target_type ;
42     typedef S source_type ;
43     typedef T result_type ;
44 
45     typedef typename mpl::if_< is_arithmetic<S>, S, S const&>::type argument_type ;
46 
47     typedef typename mpl::if_<subranged,S,T>::type supertype ;
48     typedef typename mpl::if_<subranged,T,S>::type subtype   ;
49   } ;
50 
51   //-------------------------------------------------------------------
52   // Implementation of the Conversion Traits for T == S
53   //
54   // This is a VISIBLE base class of the user-level conversion_traits<> class.
55   //-------------------------------------------------------------------
56   template<class N>
57   struct trivial_traits_impl
58   {
59     typedef typename get_int_float_mixture  <N,N>::type int_float_mixture ;
60     typedef typename get_sign_mixture       <N,N>::type sign_mixture ;
61     typedef typename get_udt_builtin_mixture<N,N>::type udt_builtin_mixture ;
62 
63     typedef mpl::false_ subranged ;
64     typedef mpl::true_  trivial ;
65 
66     typedef N        target_type ;
67     typedef N        source_type ;
68     typedef N const& result_type ;
69     typedef N const& argument_type ;
70 
71     typedef N supertype ;
72     typedef N subtype  ;
73 
74   } ;
75 
76   //-------------------------------------------------------------------
77   // Top level implementation selector.
78   //-------------------------------------------------------------------
79   template<class T, class S>
80   struct get_conversion_traits
81   {
82     typedef typename remove_cv<T>::type target_type ;
83     typedef typename remove_cv<S>::type source_type ;
84 
85     typedef typename is_same<target_type,source_type>::type is_trivial ;
86 
87     typedef trivial_traits_impl    <target_type>             trivial_imp ;
88     typedef non_trivial_traits_impl<target_type,source_type> non_trivial_imp ;
89 
90     typedef typename mpl::if_<is_trivial,trivial_imp,non_trivial_imp>::type type ;
91   } ;
92 
93 } } } // namespace boost::numeric::convdetail
94 
95 #endif
96 
97 
98