boost/boost/type_traits/is_pointer.hpp

   1
   2 // (C) Copyright Dave Abrahams, Steve Cleary, Beman Dawes, Howard
   3 // Hinnant & John Maddock 2000.  Permission to copy, use, modify,
   4 // sell and distribute this software is granted provided this
   5 // copyright notice appears in all copies. This software is provided
   6 // "as is" without express or implied warranty, and with no claim as
   7 // to its suitability for any purpose.
   8 //
   9 // See http://www.boost.org for most recent version including documentation.
  10
  11 #ifndef BOOST_TT_IS_POINTER_HPP_INCLUDED
  12 #define BOOST_TT_IS_POINTER_HPP_INCLUDED
  13
  14 #include "boost/type_traits/is_member_pointer.hpp"
  15 #include "boost/type_traits/detail/ice_and.hpp"
  16 #include "boost/type_traits/detail/ice_not.hpp"
  17 #include "boost/type_traits/config.hpp"
  18
  19 #ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
  20 #   include "boost/type_traits/is_reference.hpp"
  21 #   include "boost/type_traits/is_array.hpp"
  22 #   include "boost/type_traits/detail/is_function_ptr_tester.hpp"
  23 #   include "boost/type_traits/detail/false_result.hpp"
  24 #   include "boost/type_traits/detail/ice_or.hpp"
  25 #endif
  26
  27 // should be the last #include
  28 #include "boost/type_traits/detail/bool_trait_def.hpp"
  29
  30 namespace boost {
  31
  32 #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
  33
  34 namespace detail {
  35
  36 template< typename T > struct is_pointer_helper
  37 {
  38     BOOST_STATIC_CONSTANT(bool, value = false);
  39 };
  40
  41 #   define TT_AUX_BOOL_TRAIT_HELPER_PARTIAL_SPEC(helper,sp,result) \
  42 template< typename T > struct helper<sp> \
  43 { \
  44     BOOST_STATIC_CONSTANT(bool, value = result); \
  45 }; \
  46 /**/
  47
  48 TT_AUX_BOOL_TRAIT_HELPER_PARTIAL_SPEC(is_pointer_helper,T*,true)
  49 TT_AUX_BOOL_TRAIT_HELPER_PARTIAL_SPEC(is_pointer_helper,T* const,true)
  50 TT_AUX_BOOL_TRAIT_HELPER_PARTIAL_SPEC(is_pointer_helper,T* volatile,true)
  51 TT_AUX_BOOL_TRAIT_HELPER_PARTIAL_SPEC(is_pointer_helper,T* const volatile,true)
  52
  53 #   undef TT_AUX_BOOL_TRAIT_HELPER_PARTIAL_SPEC
  54
  55 template< typename T >
  56 struct is_pointer_impl
  57 {
  58     BOOST_STATIC_CONSTANT(bool, value =
  59         (::boost::type_traits::ice_and<
  60               ::boost::detail::is_pointer_helper<T>::value
  61             , ::boost::type_traits::ice_not<
  62                 ::boost::is_member_pointer<T>::value
  63                 >::value
  64             >::value)
  65         );
  66 };
  67
  68 } // namespace detail
  69
  70 BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_pointer,T,::boost::detail::is_pointer_impl<T>::value)
  71
  72 #if defined(__BORLANDC__) && !defined(__COMO__)
  73 BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_pointer,T&,false)
  74 BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_pointer,T& const,false)
  75 BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_pointer,T& volatile,false)
  76 BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_pointer,T& const volatile,false)
  77 #endif
  78
  79 #else // no partial template specialization
  80
  81 namespace detail {
  82
  83 struct pointer_helper
  84 {
  85     pointer_helper(const volatile void*);
  86 };
  87
  88 yes_type BOOST_TT_DECL is_pointer_tester(pointer_helper);
  89 no_type BOOST_TT_DECL is_pointer_tester(...);
  90
  91 template <bool>
  92 struct is_pointer_select
  93     : ::boost::type_traits::false_result
  94 {
  95 };
  96
  97 template <>
  98 struct is_pointer_select<false>
  99 {
 100     template <typename T> struct result_
 101     {
 102         static T& make_t();
 103         BOOST_STATIC_CONSTANT(bool, value =
 104                 (::boost::type_traits::ice_or<
 105                     (1 == sizeof(is_pointer_tester(make_t()))),
 106                     (1 == sizeof(type_traits::is_function_ptr_tester(make_t())))
 107                 >::value));
 108     };
 109 };
 110
 111 template <typename T>
 112 struct is_pointer_impl
 113     : is_pointer_select<
 114           ::boost::type_traits::ice_or<
 115               ::boost::is_reference<T>::value
 116             , ::boost::is_array<T>::value
 117             >::value
 118         >::template result_<T>
 119 {
 120 };
 121
 122 BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pointer,void,false)
 123 #ifndef BOOST_NO_CV_VOID_SPECIALIZATIONS
 124 BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pointer,void const,false)
 125 BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pointer,void volatile,false)
 126 BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_pointer,void const volatile,false)
 127 #endif
 128
 129 } // namespace detail
 130
 131 BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_pointer,T,::boost::detail::is_pointer_impl<T>::value)
 132
 133 #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
 134
 135 } // namespace boost
 136
 137 #include "boost/type_traits/detail/bool_trait_undef.hpp"
 138
 139 #endif // BOOST_TT_IS_POINTER_HPP_INCLUDED