1/*=============================================================================
2 Copyright (c) 2001-2011 Joel de Guzman
3
4 Distributed under the Boost Software License, Version 1.0. (See accompanying
5 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6==============================================================================*/
7#if !defined(BOOST_SPIRIT_EXTENDED_VARIANT_AUGUST_6_2011_0859AM)
8#define BOOST_SPIRIT_EXTENDED_VARIANT_AUGUST_6_2011_0859AM
9
10#if defined(_MSC_VER)
11#pragma once
12#endif
13
14#include <boost/variant.hpp>
15#include <boost/mpl/limits/list.hpp>
16#include <boost/preprocessor/repetition/enum_params.hpp>
17#include <boost/preprocessor/repetition/enum_params_with_a_default.hpp>
18
19#if !defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
20#define BOOST_SPIRIT_EXTENDED_VARIANT_LIMIT_TYPES BOOST_MPL_LIMIT_LIST_SIZE
21#else
22#define BOOST_SPIRIT_EXTENDED_VARIANT_LIMIT_TYPES BOOST_VARIANT_LIMIT_TYPES
23#endif
24
25#define BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(T) \
26 BOOST_PP_ENUM_PARAMS(BOOST_SPIRIT_EXTENDED_VARIANT_LIMIT_TYPES, T) \
27 /**/
28
29///////////////////////////////////////////////////////////////////////////////
30namespace boost { namespace spirit
31{
32#if defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
33 template <
34 BOOST_PP_ENUM_PARAMS_WITH_A_DEFAULT(
35 BOOST_SPIRIT_EXTENDED_VARIANT_LIMIT_TYPES,
36 typename T, boost::detail::variant::void_)
37 // We should not be depending on detail::variant::void_
38 // but I'm not sure if this can fixed. Any other way is
39 // clumsy at best.
40 >
41#else
42 template <typename... Types>
43#endif
44 struct extended_variant
45 {
46 // tell spirit that this is an adapted variant
47 struct adapted_variant_tag;
48
49#if defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
50 typedef boost::variant<
51 BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(T)>
52 variant_type;
53 typedef typename variant_type::types types;
54
55 typedef extended_variant<
56 BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(T)
57 > base_type;
58#else
59 typedef boost::variant<Types...> variant_type;
60 typedef typename variant_type::types types;
61 typedef extended_variant<Types...> base_type;
62#endif
63
64 extended_variant() : var() {}
65
66 template <typename T>
67 extended_variant(T const& var)
68 : var(var) {}
69
70 template <typename T>
71 extended_variant(T& var)
72 : var(var) {}
73
74 template <typename F>
75 typename F::result_type apply_visitor(F const& v)
76 {
77 return var.apply_visitor(v);
78 }
79
80 template <typename F>
81 typename F::result_type apply_visitor(F const& v) const
82 {
83 return var.apply_visitor(v);
84 }
85
86 template <typename F>
87 typename F::result_type apply_visitor(F& v)
88 {
89 return var.apply_visitor(v);
90 }
91
92 template <typename F>
93 typename F::result_type apply_visitor(F& v) const
94 {
95 return var.apply_visitor(v);
96 }
97
98 variant_type const& get() const
99 {
100 return var;
101 }
102
103 variant_type& get()
104 {
105 return var;
106 }
107
108 void swap(extended_variant& rhs) BOOST_NOEXCEPT
109 {
110 var.swap(rhs.var);
111 }
112
113 variant_type var;
114 };
115}}
116
117namespace boost
118{
119#if defined(BOOST_VARIANT_DO_NOT_USE_VARIADIC_TEMPLATES)
120 template <typename T, BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(typename T)>
121 inline T const&
122 get(boost::spirit::extended_variant<
123 BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(T)> const& x)
124 {
125 return boost::get<T>(x.get());
126 }
127
128 template <typename T, BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(typename T)>
129 inline T&
130 get(boost::spirit::extended_variant<
131 BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(T)>& x)
132 {
133 return boost::get<T>(x.get());
134 }
135
136 template <typename T, BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(typename T)>
137 inline T const*
138 get(boost::spirit::extended_variant<
139 BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(T)> const* x)
140 {
141 return boost::get<T>(&x->get());
142 }
143
144 template <typename T, BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(typename T)>
145 inline T*
146 get(boost::spirit::extended_variant<
147 BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS(T)>* x)
148 {
149 return boost::get<T>(&x->get());
150 }
151#else
152 template <typename T, typename... Types>
153 inline T const&
154 get(boost::spirit::extended_variant<Types...> const& x)
155 {
156 return boost::get<T>(x.get());
157 }
158
159 template <typename T, typename... Types>
160 inline T&
161 get(boost::spirit::extended_variant<Types...>& x)
162 {
163 return boost::get<T>(x.get());
164 }
165
166 template <typename T, typename... Types>
167 inline T const*
168 get(boost::spirit::extended_variant<Types...> const* x)
169 {
170 return boost::get<T>(&x->get());
171 }
172
173 template <typename T, typename... Types>
174 inline T*
175 get(boost::spirit::extended_variant<Types...>* x)
176 {
177 return boost::get<T>(&x->get());
178 }
179#endif
180}
181
182#undef BOOST_SPIRIT_EXTENDED_VARIANT_ENUM_PARAMS
183#undef BOOST_SPIRIT_EXTENDED_VARIANT_LIMIT_TYPES
184
185#endif
186

source code of boost/libs/spirit/include/boost/spirit/home/support/extended_variant.hpp