1 |
|
---|
2 | // (C) Copyright Dave Abrahams, Steve Cleary, Beman Dawes,
|
---|
3 | // Howard Hinnant and John Maddock 2000.
|
---|
4 | // (C) Copyright Mat Marcus, Jesse Jones and Adobe Systems Inc 2001
|
---|
5 |
|
---|
6 | // Use, modification and distribution are subject to the Boost Software License,
|
---|
7 | // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
---|
8 | // http://www.boost.org/LICENSE_1_0.txt).
|
---|
9 | //
|
---|
10 | // See http://www.boost.org/libs/type_traits for most recent version including documentation.
|
---|
11 |
|
---|
12 | // Fixed is_pointer, is_reference, is_const, is_volatile, is_same,
|
---|
13 | // is_member_pointer based on the Simulated Partial Specialization work
|
---|
14 | // of Mat Marcus and Jesse Jones. See http://opensource.adobe.com or
|
---|
15 | // http://groups.yahoo.com/group/boost/message/5441
|
---|
16 | // Some workarounds in here use ideas suggested from "Generic<Programming>:
|
---|
17 | // Mappings between Types and Values"
|
---|
18 | // by Andrei Alexandrescu (see http://www.cuj.com/experts/1810/alexandr.html).
|
---|
19 |
|
---|
20 |
|
---|
21 | #ifndef BOOST_TT_IS_CONST_HPP_INCLUDED
|
---|
22 | #define BOOST_TT_IS_CONST_HPP_INCLUDED
|
---|
23 |
|
---|
24 | #include "boost/config.hpp"
|
---|
25 |
|
---|
26 | #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
|
---|
27 | # include "boost/type_traits/detail/cv_traits_impl.hpp"
|
---|
28 | # ifdef __GNUC__
|
---|
29 | # include <boost/type_traits/is_reference.hpp>
|
---|
30 | # endif
|
---|
31 | #else
|
---|
32 | # include "boost/type_traits/is_reference.hpp"
|
---|
33 | # include "boost/type_traits/is_array.hpp"
|
---|
34 | # include "boost/type_traits/detail/yes_no_type.hpp"
|
---|
35 | # include "boost/type_traits/detail/false_result.hpp"
|
---|
36 | #endif
|
---|
37 |
|
---|
38 | // should be the last #include
|
---|
39 | #include "boost/type_traits/detail/bool_trait_def.hpp"
|
---|
40 |
|
---|
41 | namespace boost {
|
---|
42 |
|
---|
43 | #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
|
---|
44 |
|
---|
45 | //* is a type T declared const - is_const<T>
|
---|
46 | BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_const,T,::boost::detail::cv_traits_imp<T*>::is_const)
|
---|
47 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T&,false)
|
---|
48 |
|
---|
49 | #if defined(__BORLANDC__) && (__BORLANDC__ < 0x600)
|
---|
50 | // these are illegal specialisations; cv-qualifies applied to
|
---|
51 | // references have no effect according to [8.3.2p1],
|
---|
52 | // C++ Builder requires them though as it treats cv-qualified
|
---|
53 | // references as distinct types...
|
---|
54 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T& const,false)
|
---|
55 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T& volatile,false)
|
---|
56 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T& const volatile,false)
|
---|
57 | #endif
|
---|
58 |
|
---|
59 | #if defined(__GNUC__) && (__GNUC__ < 3)
|
---|
60 | // special case for gcc where illegally cv-qualified reference types can be
|
---|
61 | // generated in some corner cases:
|
---|
62 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T const,!(::boost::is_reference<T>::value))
|
---|
63 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T volatile const,!(::boost::is_reference<T>::value))
|
---|
64 | #endif
|
---|
65 |
|
---|
66 | #else
|
---|
67 |
|
---|
68 | namespace detail {
|
---|
69 |
|
---|
70 | using ::boost::type_traits::yes_type;
|
---|
71 | using ::boost::type_traits::no_type;
|
---|
72 |
|
---|
73 | yes_type is_const_tester(const volatile void*);
|
---|
74 | no_type is_const_tester(volatile void *);
|
---|
75 |
|
---|
76 | template <bool is_ref, bool array>
|
---|
77 | struct is_const_helper
|
---|
78 | : ::boost::type_traits::false_result
|
---|
79 | {
|
---|
80 | };
|
---|
81 |
|
---|
82 | template <>
|
---|
83 | struct is_const_helper<false,false>
|
---|
84 | {
|
---|
85 | template <typename T> struct result_
|
---|
86 | {
|
---|
87 | static T* t;
|
---|
88 | BOOST_STATIC_CONSTANT(bool, value = (
|
---|
89 | sizeof(detail::yes_type) == sizeof(detail::is_const_tester(t))
|
---|
90 | ));
|
---|
91 | };
|
---|
92 | };
|
---|
93 |
|
---|
94 | template <>
|
---|
95 | struct is_const_helper<false,true>
|
---|
96 | {
|
---|
97 | template <typename T> struct result_
|
---|
98 | {
|
---|
99 | static T t;
|
---|
100 | BOOST_STATIC_CONSTANT(bool, value = (
|
---|
101 | sizeof(detail::yes_type) == sizeof(detail::is_const_tester(&t))
|
---|
102 | ));
|
---|
103 | };
|
---|
104 | };
|
---|
105 |
|
---|
106 | template <typename T>
|
---|
107 | struct is_const_impl
|
---|
108 | : is_const_helper<
|
---|
109 | is_reference<T>::value
|
---|
110 | , is_array<T>::value
|
---|
111 | >::template result_<T>
|
---|
112 | {
|
---|
113 | };
|
---|
114 |
|
---|
115 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_const,void,false)
|
---|
116 | #ifndef BOOST_NO_CV_VOID_SPECIALIZATIONS
|
---|
117 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_const,void const,true)
|
---|
118 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_const,void volatile,false)
|
---|
119 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_const,void const volatile,true)
|
---|
120 | #endif
|
---|
121 |
|
---|
122 | } // namespace detail
|
---|
123 |
|
---|
124 | //* is a type T declared const - is_const<T>
|
---|
125 | BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_const,T,::boost::detail::is_const_impl<T>::value)
|
---|
126 |
|
---|
127 | #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
|
---|
128 |
|
---|
129 | } // namespace boost
|
---|
130 |
|
---|
131 | #include "boost/type_traits/detail/bool_trait_undef.hpp"
|
---|
132 |
|
---|
133 | #endif // BOOST_TT_IS_CONST_HPP_INCLUDED
|
---|
134 |
|
---|