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_lvalue_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_LVALUE_REFERENCE_HPP_INCLUDED |
---|
22 | #define BOOST_TT_IS_LVALUE_REFERENCE_HPP_INCLUDED |
---|
23 | |
---|
24 | #include <boost/type_traits/config.hpp> |
---|
25 | |
---|
26 | #ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION |
---|
27 | # include <boost/type_traits/detail/yes_no_type.hpp> |
---|
28 | # include <boost/type_traits/detail/wrap.hpp> |
---|
29 | #endif |
---|
30 | |
---|
31 | // should be the last #include |
---|
32 | #include <boost/type_traits/detail/bool_trait_def.hpp> |
---|
33 | |
---|
34 | namespace boost { |
---|
35 | |
---|
36 | #if defined( __CODEGEARC__ ) |
---|
37 | BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_lvalue_reference,T,__is_reference(T)) |
---|
38 | #elif !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) |
---|
39 | |
---|
40 | BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_lvalue_reference,T,false) |
---|
41 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_lvalue_reference,T&,true) |
---|
42 | |
---|
43 | #if defined(BOOST_ILLEGAL_CV_REFERENCES) |
---|
44 | // these are illegal specialisations; cv-qualifies applied to |
---|
45 | // references have no effect according to [8.3.2p1], |
---|
46 | // C++ Builder requires them though as it treats cv-qualified |
---|
47 | // references as distinct types... |
---|
48 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_lvalue_reference,T& const,true) |
---|
49 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_lvalue_reference,T& volatile,true) |
---|
50 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_lvalue_reference,T& const volatile,true) |
---|
51 | #endif |
---|
52 | |
---|
53 | #if defined(__GNUC__) && (__GNUC__ < 3) |
---|
54 | // these allow us to work around illegally cv-qualified reference |
---|
55 | // types. |
---|
56 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_lvalue_reference,T const ,::boost::is_lvalue_reference<T>::value) |
---|
57 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_lvalue_reference,T volatile ,::boost::is_lvalue_reference<T>::value) |
---|
58 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_lvalue_reference,T const volatile ,::boost::is_lvalue_reference<T>::value) |
---|
59 | // However, the above specializations confuse gcc 2.96 unless we also |
---|
60 | // supply these specializations for array types |
---|
61 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_2(typename T,unsigned long N,is_lvalue_reference,T[N],false) |
---|
62 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_2(typename T,unsigned long N,is_lvalue_reference,const T[N],false) |
---|
63 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_2(typename T,unsigned long N,is_lvalue_reference,volatile T[N],false) |
---|
64 | BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_2(typename T,unsigned long N,is_lvalue_reference,const volatile T[N],false) |
---|
65 | #endif |
---|
66 | |
---|
67 | #else |
---|
68 | |
---|
69 | #ifdef BOOST_MSVC |
---|
70 | # pragma warning(push) |
---|
71 | # pragma warning(disable: 4181 4097) |
---|
72 | #endif |
---|
73 | |
---|
74 | namespace detail { |
---|
75 | |
---|
76 | using ::boost::type_traits::yes_type; |
---|
77 | using ::boost::type_traits::no_type; |
---|
78 | using ::boost::type_traits::wrap; |
---|
79 | |
---|
80 | template <class T> T&(* is_lvalue_reference_helper1(wrap<T>) )(wrap<T>); |
---|
81 | char is_lvalue_reference_helper1(...); |
---|
82 | |
---|
83 | template <class T> no_type is_lvalue_reference_helper2(T&(*)(wrap<T>)); |
---|
84 | yes_type is_lvalue_reference_helper2(...); |
---|
85 | |
---|
86 | template <typename T> |
---|
87 | struct is_lvalue_reference_impl |
---|
88 | { |
---|
89 | BOOST_STATIC_CONSTANT( |
---|
90 | bool, value = sizeof( |
---|
91 | ::boost::detail::is_lvalue_reference_helper2( |
---|
92 | ::boost::detail::is_lvalue_reference_helper1(::boost::type_traits::wrap<T>()))) == 1 |
---|
93 | ); |
---|
94 | }; |
---|
95 | |
---|
96 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_lvalue_reference,void,false) |
---|
97 | #ifndef BOOST_NO_CV_VOID_SPECIALIZATIONS |
---|
98 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_lvalue_reference,void const,false) |
---|
99 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_lvalue_reference,void volatile,false) |
---|
100 | BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_lvalue_reference,void const volatile,false) |
---|
101 | #endif |
---|
102 | |
---|
103 | } // namespace detail |
---|
104 | |
---|
105 | BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_lvalue_reference,T,::boost::detail::is_lvalue_reference_impl<T>::value) |
---|
106 | |
---|
107 | #ifdef BOOST_MSVC |
---|
108 | # pragma warning(pop) |
---|
109 | #endif |
---|
110 | |
---|
111 | #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION |
---|
112 | |
---|
113 | } // namespace boost |
---|
114 | |
---|
115 | #include <boost/type_traits/detail/bool_trait_undef.hpp> |
---|
116 | |
---|
117 | #endif // BOOST_TT_IS_REFERENCE_HPP_INCLUDED |
---|
118 | |
---|