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034d0a2 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 | #ifndef BOOST_SERIALIZATION_STD_VARIANT_HPP
#define BOOST_SERIALIZATION_STD_VARIANT_HPP
// MS compatible compilers support #pragma once
#if defined(_MSC_VER)
# pragma once
#endif
/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// variant.hpp - non-intrusive serialization of variant types
//
// copyright (c) 2019 Samuel Debionne, ESRF
//
// Use, modification and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org for updates, documentation, and revision history.
//
// Widely inspired form boost::variant serialization
//
#include <boost/serialization/throw_exception.hpp>
#include <variant>
#include <boost/archive/archive_exception.hpp>
#include <boost/serialization/split_free.hpp>
#include <boost/serialization/serialization.hpp>
#include <boost/serialization/nvp.hpp>
namespace boost {
namespace serialization {
template<class Archive>
struct std_variant_save_visitor
{
std_variant_save_visitor(Archive& ar) :
m_ar(ar)
{}
template<class T>
void operator()(T const & value) const
{
m_ar << BOOST_SERIALIZATION_NVP(value);
}
private:
Archive & m_ar;
};
template<class Archive>
struct std_variant_load_visitor
{
std_variant_load_visitor(Archive& ar) :
m_ar(ar)
{}
template<class T>
void operator()(T & value) const
{
m_ar >> BOOST_SERIALIZATION_NVP(value);
}
private:
Archive & m_ar;
};
template<class Archive, class ...Types>
void save(
Archive & ar,
std::variant<Types...> const & v,
unsigned int /*version*/
){
const std::size_t which = v.index();
ar << BOOST_SERIALIZATION_NVP(which);
std_variant_save_visitor<Archive> visitor(ar);
std::visit(visitor, v);
}
// Minimalist metaprogramming for handling parameter pack
namespace mp {
namespace detail {
template <typename Seq>
struct front_impl;
template <template <typename...> class Seq, typename T, typename... Ts>
struct front_impl<Seq<T, Ts...>> {
using type = T;
};
template <typename Seq>
struct pop_front_impl;
template <template <typename...> class Seq, typename T, typename... Ts>
struct pop_front_impl<Seq<T, Ts...>> {
using type = Seq<Ts...>;
};
} //namespace detail
template <typename... Ts>
struct typelist {};
template <typename Seq>
using front = typename detail::front_impl<Seq>::type;
template <typename Seq>
using pop_front = typename detail::pop_front_impl<Seq>::type;
} // namespace mp
template<std::size_t N, class Seq>
struct variant_impl
{
template<class Archive, class V>
static void load (
Archive & ar,
std::size_t which,
V & v,
const unsigned int version
){
if(which == 0){
// note: A non-intrusive implementation (such as this one)
// necessary has to copy the value. This wouldn't be necessary
// with an implementation that de-serialized to the address of the
// aligned storage included in the variant.
using type = mp::front<Seq>;
type value;
ar >> BOOST_SERIALIZATION_NVP(value);
v = std::move(value);
type * new_address = & std::get<type>(v);
ar.reset_object_address(new_address, & value);
return;
}
//typedef typename mpl::pop_front<S>::type type;
using types = mp::pop_front<Seq>;
variant_impl<N - 1, types>::load(ar, which - 1, v, version);
}
};
template<class Seq>
struct variant_impl<0, Seq>
{
template<class Archive, class V>
static void load (
Archive & /*ar*/,
std::size_t /*which*/,
V & /*v*/,
const unsigned int /*version*/
){}
};
template<class Archive, class... Types>
void load(
Archive & ar,
std::variant<Types...>& v,
const unsigned int version
){
std::size_t which;
ar >> BOOST_SERIALIZATION_NVP(which);
if(which >= sizeof...(Types))
// this might happen if a type was removed from the list of variant types
boost::serialization::throw_exception(
boost::archive::archive_exception(
boost::archive::archive_exception::unsupported_version
)
);
variant_impl<sizeof...(Types), mp::typelist<Types...>>::load(ar, which, v, version);
}
template<class Archive,class... Types>
inline void serialize(
Archive & ar,
std::variant<Types...> & v,
const unsigned int file_version
){
split_free(ar,v,file_version);
}
// Specialization for std::monostate
template<class Archive>
void serialize(Archive &ar, std::monostate &, const unsigned int /*version*/)
{}
} // namespace serialization
} // namespace boost
//template<typename T0_, BOOST_VARIANT_ENUM_SHIFTED_PARAMS(typename T)>
#include <boost/serialization/tracking.hpp>
namespace boost {
namespace serialization {
template<class... Types>
struct tracking_level<
std::variant<Types...>
>{
typedef mpl::integral_c_tag tag;
typedef mpl::int_< ::boost::serialization::track_always> type;
BOOST_STATIC_CONSTANT(int, value = type::value);
};
} // namespace serialization
} // namespace boost
#endif //BOOST_SERIALIZATION_VARIANT_HPP
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