boost/type_traits/msvc/remove_const.hpp

   1 // Copyright (C) 2004 Peder Holt
   2 // Use, modification and distribution is subject to the Boost Software
   3 // License, Version 1.0. (http://www.boost.org/LICENSE_1_0.txt)
   4
   5 #ifndef BOOST_TYPE_TRAITS_MSVC_REMOVE_CONST_HOLT_2004_0828
   6 #define BOOST_TYPE_TRAITS_MSVC_REMOVE_CONST_HOLT_2004_0828
   7
   8 #include <boost/type_traits/msvc/typeof.hpp>
   9 #include <boost/type_traits/is_volatile.hpp>
  10 #include <boost/type_traits/is_const.hpp>
  11 #include <boost/type_traits/is_pointer.hpp>
  12 #include <boost/type_traits/is_array.hpp>
  13
  14 namespace boost {
  15     namespace detail {
  16         template<bool IsPointer,bool IsArray,bool IsConst,bool IsVolatile>
  17         struct remove_const_impl_typeof {
  18             template<typename T,typename ID>
  19             struct inner {
  20                 typedef T type;
  21             };
  22             template<typename T>
  23             struct transform_type {
  24                 typedef T type;
  25             };
  26         };
  27         template<> //Const
  28         struct remove_const_impl_typeof<false,false,true,false> {
  29             template<typename T,typename ID>
  30             struct inner {
  31                 template<typename U>
  32                 static msvc_register_type<U,ID> test(U const&(*)());
  33                 static msvc_register_type<T,ID> test(...);
  34                 BOOST_STATIC_CONSTANT(unsigned,register_test=sizeof(test( (T(*)())(NULL) ) ));
  35                 typedef typename msvc_extract_type<ID>::id2type::type type;
  36             };
  37             template<typename T>
  38             struct transform_type {
  39                 typedef T& type;
  40             };
  41         };
  42         template<> //CV
  43         struct remove_const_impl_typeof<false,false,true,true> {
  44             template<typename T,typename ID>
  45             struct inner {
  46                 template<typename U>
  47                 static msvc_register_type<U volatile,ID> test(U const volatile&(*)());
  48                 static msvc_register_type<T,ID> test(...);
  49                 BOOST_STATIC_CONSTANT(unsigned,register_test=sizeof(test( (T(*)())(NULL) ) ));
  50                 typedef typename msvc_extract_type<ID>::id2type::type type;
  51             };
  52             template<typename T>
  53             struct transform_type {
  54                 typedef T& type;
  55             };
  56         };
  57         template<> //Const Pointer
  58         struct remove_const_impl_typeof<true,false,true,false> {
  59             template<typename T,typename ID>
  60             struct inner {
  61                 template<typename U>
  62                 static msvc_register_type<U,ID> test(void(*)(U const[]));
  63                 static msvc_register_type<T,ID> test(...);
  64                 BOOST_STATIC_CONSTANT(unsigned,register_test=sizeof(test( (void(*)(T))(NULL) ) ));
  65                 typedef typename msvc_extract_type<ID>::id2type::type type;
  66             };
  67             template<typename T>
  68             struct transform_type {
  69                 typedef T type[];
  70             };
  71         };
  72         template<> //CV Pointer
  73         struct remove_const_impl_typeof<true,false,true,true> {
  74             template<typename T,typename ID>
  75             struct inner {
  76                 template<typename U>
  77                 static msvc_register_type<U volatile,ID> test(void(*)(U const volatile[]));
  78                 static msvc_register_type<T,ID> test(...);
  79                 BOOST_STATIC_CONSTANT(unsigned,register_test=sizeof(test( (void(*)(T))(NULL) ) ));
  80                 typedef typename msvc_extract_type<ID>::id2type::type type;
  81             };
  82             template<typename T>
  83             struct transform_type {
  84                 typedef T type[];
  85             };
  86         };
  87         template<> //Const Array
  88         struct remove_const_impl_typeof<false,true,true,false> {
  89             template<typename T,typename ID>
  90             struct inner {
  91                 BOOST_STATIC_CONSTANT(unsigned,value=(sizeof(T)/sizeof((*((T*)NULL))[0])));
  92
  93                 template<typename U>
  94                 static msvc_register_type<U[value],ID> test(void(*)(U const[]));
  95                 static msvc_register_type<T,ID> test(...);
  96                 BOOST_STATIC_CONSTANT(unsigned,register_test=sizeof(test( (void(*)(T))(NULL) ) ));
  97                 typedef typename msvc_extract_type<ID>::id2type::type type;
  98             };
  99             template<typename T>
 100             struct transform_type {
 101                 typedef T type;
 102             };
 103         };
 104
 105         template<> //CV Array
 106         struct remove_const_impl_typeof<false,true,true,true> {
 107             template<typename T,typename ID>
 108             struct inner {
 109                 BOOST_STATIC_CONSTANT(unsigned,value=(sizeof(T)/sizeof((*((T*)NULL))[0])));
 110
 111                 template<typename U>
 112                 static msvc_register_type<U volatile[value],ID> test(void(*)(U const volatile[]));
 113                 static msvc_register_type<T,ID> test(...);
 114                 BOOST_STATIC_CONSTANT(unsigned,register_test=sizeof(test( (void(*)(T))(NULL) ) ));
 115                 typedef typename msvc_extract_type<ID>::id2type::type type;
 116             };
 117             template<typename T>
 118             struct transform_type {
 119                 typedef T type;
 120             };
 121         };
 122
 123     } //namespace detail
 124
 125     template<typename T>
 126     struct remove_const {
 127         typedef boost::detail::remove_const_impl_typeof<
 128             boost::is_pointer<T>::value,
 129             boost::is_array<T>::value,
 130             boost::is_const<T>::value,
 131             boost::is_volatile<T>::value
 132         > remove_const_type;
 133         typedef typename
 134             remove_const_type::template inner<
 135                 typename remove_const_type::template transform_type<T>::type,
 136                 remove_const<T>
 137             >::type
 138         type;
 139         BOOST_MPL_AUX_LAMBDA_SUPPORT(1,remove_const,T)
 140     };
 141 }//namespace boost
 142
 143 #endif //BOOST_TYPE_TRAITS_MSVC_REMOVE_CONST_HOLT_2004_0828