sl@0: /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
sl@0: 
sl@0: // (C) Copyright 2002-4 Pavel Vozenilek . 
sl@0: // Use, modification and distribution is subject to the Boost Software
sl@0: // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
sl@0: // http://www.boost.org/LICENSE_1_0.txt)
sl@0: 
sl@0: // Provides non-intrusive serialization for boost::optional.
sl@0: 
sl@0: #ifndef BOOST_SERIALIZATION_OPTIONAL_HPP_
sl@0: #define BOOST_SERIALIZATION_OPTIONAL_HPP_
sl@0: 
sl@0: #if defined(_MSC_VER) && (_MSC_VER >= 1020)
sl@0: # pragma once
sl@0: #endif
sl@0: 
sl@0: #include <boost/config.hpp>
sl@0: 
sl@0: #include <boost/optional.hpp>
sl@0: #include <boost/serialization/split_free.hpp>
sl@0: #include <boost/serialization/level.hpp>
sl@0: #include <boost/serialization/nvp.hpp>
sl@0: #include <boost/serialization/detail/stack_constructor.hpp>
sl@0: 
sl@0: // function specializations must be defined in the appropriate
sl@0: // namespace - boost::serialization
sl@0: namespace boost { 
sl@0: namespace serialization {
sl@0: 
sl@0: template<class Archive, class T>
sl@0: void save(
sl@0:     Archive & ar, 
sl@0:     const boost::optional<T> & t, 
sl@0:     const unsigned int /*version*/
sl@0: ){
sl@0:     const bool tflag = t.is_initialized();
sl@0:     ar << boost::serialization::make_nvp("initialized", tflag);
sl@0:     if (tflag){
sl@0:         if(3 < ar.get_library_version()){
sl@0:             const int v = version<T>::value;
sl@0:             ar << make_nvp("item_version", v);
sl@0:         }
sl@0:         ar << boost::serialization::make_nvp("value", *t);
sl@0:     }
sl@0: }
sl@0: 
sl@0: template<class Archive, class T>
sl@0: void load(
sl@0:     Archive & ar, 
sl@0:     boost::optional<T> & t, 
sl@0:     const unsigned int /*version*/
sl@0: ){
sl@0:     bool tflag;
sl@0:     ar >> boost::serialization::make_nvp("initialized", tflag);
sl@0:     if (tflag){
sl@0:         unsigned int v;
sl@0:         if(3 < ar.get_library_version()){
sl@0:             ar >> make_nvp("item_version", v);
sl@0:         }
sl@0:         detail::stack_construct<Archive, T> aux(ar, v);
sl@0:         ar >> boost::serialization::make_nvp("value", aux.reference());
sl@0:         t.reset(aux.reference());
sl@0:     }
sl@0:     else {
sl@0:         t.reset();
sl@0:     }
sl@0: }
sl@0: 
sl@0: template<class Archive, class T>
sl@0: void serialize(
sl@0:     Archive & ar, 
sl@0:     boost::optional<T> & t, 
sl@0:     const unsigned int version
sl@0: ){
sl@0:     boost::serialization::split_free(ar, t, version);
sl@0: }
sl@0: 
sl@0: // the following would be slightly more efficient.  But it
sl@0: // would mean that archives created with programs that support
sl@0: // TPS wouldn't be readable by programs that don't support TPS.
sl@0: // Hence we decline to support this otherwise convenient optimization.
sl@0: //#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
sl@0: #if 0
sl@0: 
sl@0: template <class T>
sl@0: struct implementation_level<optional<T> >
sl@0: {
sl@0:     typedef mpl::integral_c_tag tag;
sl@0:     typedef mpl::int_<boost::serialization::object_serializable> type;
sl@0:     BOOST_STATIC_CONSTANT(
sl@0:         int , 
sl@0:         value = boost::serialization::implementation_level::type::value
sl@0:     );
sl@0: };
sl@0: 
sl@0: template<class T>
sl@0: struct tracking_level<optional<T> >
sl@0: {
sl@0:     typedef mpl::integral_c_tag tag;
sl@0:     typedef mpl::int_<boost::serialization::track_never> type;
sl@0:     BOOST_STATIC_CONSTANT(
sl@0:         int , 
sl@0:         value = boost::serialization::tracking_level::type::value
sl@0:     );
sl@0: };
sl@0: 
sl@0: #endif
sl@0: 
sl@0: } // serialization
sl@0: } // namespace boost
sl@0: 
sl@0: #endif // BOOST_SERIALIZATION_OPTIONAL_HPP_