1
// Boost.TypeErasure library
3
// Copyright 2011 Steven Watanabe
5
// Distributed under the Boost Software License Version 1.0. (See
6
// accompanying file LICENSE_1_0.txt or copy at
7
// http://www.boost.org/LICENSE_1_0.txt)
9
// $Id: vtable.hpp 83248 2013-03-02 18:15:06Z steven_watanabe $
11
#if !defined(BOOST_PP_IS_ITERATING)
13
#ifndef BOOST_TYPE_ERASURE_DETAIL_VTABLE_HPP_INCLUDED
14
#define BOOST_TYPE_ERASURE_DETAIL_VTABLE_HPP_INCLUDED
16
#include <boost/config.hpp>
17
#include <boost/mpl/at.hpp>
18
#include <boost/mpl/size.hpp>
19
#include <boost/preprocessor/cat.hpp>
20
#include <boost/preprocessor/iteration/iterate.hpp>
21
#include <boost/preprocessor/repetition/enum.hpp>
22
#include <boost/preprocessor/repetition/enum_params.hpp>
23
#include <boost/preprocessor/repetition/enum_trailing.hpp>
24
#include <boost/preprocessor/repetition/enum_trailing_params.hpp>
25
#include <boost/preprocessor/repetition/repeat.hpp>
26
#include <boost/type_erasure/detail/rebind_placeholders.hpp>
27
#include <boost/type_erasure/config.hpp>
30
namespace type_erasure {
33
#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CONSTEXPR) && !defined(BOOST_NO_DEFAULTED_FUNCTIONS)
36
struct stored_arg_pack;
38
template<class It, class End, class... T>
39
struct make_arg_pack_impl
41
typedef typename make_arg_pack_impl<
42
typename ::boost::mpl::next<It>::type,
45
typename ::boost::mpl::deref<It>::type
49
template<class End, class... T>
50
struct make_arg_pack_impl<End, End, T...>
52
typedef stored_arg_pack<T...> type;
58
typedef typename make_arg_pack_impl<
59
typename ::boost::mpl::begin<Seq>::type,
60
typename ::boost::mpl::end<Seq>::type
65
struct make_vtable_impl;
70
typedef typename ::boost::type_erasure::detail::make_vtable_impl<
71
typename ::boost::type_erasure::detail::make_arg_pack<Seq>::type
75
template<class Table, class Args>
76
struct make_vtable_init_impl;
78
template<class Seq, class Table>
79
struct make_vtable_init
81
typedef typename make_vtable_init_impl<
83
typename ::boost::type_erasure::detail::make_arg_pack<Seq>::type
90
typename T::type value;
91
vtable_entry() = default;
92
constexpr vtable_entry(typename T::type arg) : value(arg) {}
96
struct compare_vtable;
99
struct compare_vtable<> {
101
static bool apply(const S& s1, const S& s2)
107
template<class T0, class... T>
108
struct compare_vtable<T0, T...> {
110
static bool apply(const S& s1, const S& s2)
112
return static_cast<const vtable_entry<T0>&>(s1).value ==
113
static_cast<const vtable_entry<T0>&>(s2).value &&
114
compare_vtable<T...>::apply(s1, s2);
119
struct vtable_storage : vtable_entry<T>...
121
vtable_storage() = default;
123
constexpr vtable_storage(typename T::type... arg)
124
: vtable_entry<T>(arg)... {}
126
template<class Bindings, class Src>
127
void convert_from(const Src& src)
129
*this = vtable_storage(
131
(typename ::boost::type_erasure::detail::rebind_placeholders<
136
bool operator==(const vtable_storage& other) const
137
{ return compare_vtable<T...>::apply(*this, other); }
140
typename U::type lookup(U*) const
142
return static_cast<const vtable_entry<U>*>(this)->value;
146
// Provide this specialization manually.
147
// gcc 4.7.2 fails to instantiate the primary template.
149
struct vtable_storage<>
151
vtable_storage() = default;
153
template<class Bindings, class Src>
154
void convert_from(const Src& src) {}
156
bool operator==(const vtable_storage& other) const
161
struct make_vtable_impl<stored_arg_pack<T...> >
163
typedef vtable_storage<T...> type;
166
template<class Table, class... T>
169
static constexpr Table value = Table(T::value...);
172
template<class Table, class... T>
173
constexpr Table vtable_init<Table, T...>::value;
175
template<class Table, class... T>
176
struct make_vtable_init_impl<Table, stored_arg_pack<T...> >
178
typedef vtable_init<Table, T...> type;
184
struct make_vtable_impl;
189
typedef typename make_vtable_impl<
190
(::boost::mpl::size<Seq>::value)>::template apply<Seq>::type type;
194
struct make_vtable_init_impl;
196
template<class Seq, class Table>
197
struct make_vtable_init
199
typedef typename make_vtable_init_impl<
200
(::boost::mpl::size<Seq>::value)>::template apply<Seq, Table>::type type;
203
#define BOOST_PP_FILENAME_1 <boost/type_erasure/detail/vtable.hpp>
204
#define BOOST_PP_ITERATION_LIMITS (0, BOOST_TYPE_ERASURE_MAX_FUNCTIONS)
205
#include BOOST_PP_ITERATE()
217
#define N BOOST_PP_ITERATION()
219
#define BOOST_TYPE_ERASURE_VTABLE_ENTRY(z, n, data) \
220
typename BOOST_PP_CAT(T, n)::type BOOST_PP_CAT(t, n); \
221
typename BOOST_PP_CAT(T, n)::type lookup(BOOST_PP_CAT(T, n)*) const \
223
return BOOST_PP_CAT(t, n); \
226
#define BOOST_TYPE_ERASURE_VTABLE_COMPARE(z, n, data) \
227
&& BOOST_PP_CAT(t, n) == other.BOOST_PP_CAT(t, n)
229
#define BOOST_TYPE_ERASURE_VTABLE_INIT(z, n, data) \
230
BOOST_PP_CAT(data, n)::value
232
#define BOOST_TYPE_ERASURE_AT(z, n, data) \
233
typename ::boost::mpl::at_c<data, n>::type
235
#define BOOST_TYPE_ERASURE_CONVERT_ELEMENT(z, n, data) \
236
BOOST_PP_CAT(t, n) = src.lookup( \
237
(typename ::boost::type_erasure::detail::rebind_placeholders< \
238
BOOST_PP_CAT(T, n), Bindings \
243
template<BOOST_PP_ENUM_PARAMS(N, class T)>
245
template<class D = void>
247
struct BOOST_PP_CAT(vtable_storage, N)
249
BOOST_PP_REPEAT(N, BOOST_TYPE_ERASURE_VTABLE_ENTRY, ~)
251
template<class Bindings, class Src>
252
void convert_from(const Src& src)
254
BOOST_PP_REPEAT(N, BOOST_TYPE_ERASURE_CONVERT_ELEMENT, ~)
257
bool operator==(const BOOST_PP_CAT(vtable_storage, N)& other) const
258
{ return true BOOST_PP_REPEAT(N, BOOST_TYPE_ERASURE_VTABLE_COMPARE, ~); }
262
struct make_vtable_impl<N>
267
typedef ::boost::type_erasure::detail::BOOST_PP_CAT(vtable_storage, N)<
268
BOOST_PP_ENUM(N, BOOST_TYPE_ERASURE_AT, Seq)
272
template<class Table BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)>
273
struct BOOST_PP_CAT(vtable_init, N)
275
static const Table value;
278
template<class Table BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)>
279
const Table BOOST_PP_CAT(vtable_init, N)<
280
Table BOOST_PP_ENUM_TRAILING_PARAMS(N, T)>::value =
282
BOOST_PP_ENUM(N, BOOST_TYPE_ERASURE_VTABLE_INIT, T)
286
struct make_vtable_init_impl<N>
288
template<class Seq, class Table>
291
typedef ::boost::type_erasure::detail::BOOST_PP_CAT(vtable_init, N)<
293
BOOST_PP_ENUM_TRAILING(N, BOOST_TYPE_ERASURE_AT, Seq)
298
#undef BOOST_TYPE_ERASURE_CONVERT_ELEMENT
299
#undef BOOST_TYPE_ERASURE_AT
300
#undef BOOST_TYPE_ERASURE_VTABLE_INIT
301
#undef BOOST_TYPE_ERASURE_VTABLE_COMPARE
302
#undef BOOST_TYPE_ERASURE_VTABLE_ENTRY