Imported existing code

libraries/include/boost/serialization/optional.hpp

@@ -0,0 +1,113 @@
+/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
+
+// (C) Copyright 2002-4 Pavel Vozenilek . 
+// 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)
+
+// Provides non-intrusive serialization for boost::optional.
+
+#ifndef BOOST_SERIALIZATION_OPTIONAL_HPP_
+#define BOOST_SERIALIZATION_OPTIONAL_HPP_
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+#include <boost/config.hpp>
+
+#include <boost/optional.hpp>
+#include <boost/serialization/split_free.hpp>
+#include <boost/serialization/level.hpp>
+#include <boost/serialization/nvp.hpp>
+#include <boost/serialization/version.hpp>
+#include <boost/serialization/detail/stack_constructor.hpp>
+
+// function specializations must be defined in the appropriate
+// namespace - boost::serialization
+namespace boost { 
+namespace serialization {
+
+template<class Archive, class T>
+void save(
+    Archive & ar, 
+    const boost::optional<T> & t, 
+    const unsigned int /*version*/
+){
+    const bool tflag = t.is_initialized();
+    ar << boost::serialization::make_nvp("initialized", tflag);
+    if (tflag){
+        if(3 < ar.get_library_version()){
+            const int v = version<T>::value;
+            ar << boost::serialization::make_nvp("item_version", v);
+        }
+        ar << boost::serialization::make_nvp("value", *t);
+    }
+}
+
+template<class Archive, class T>
+void load(
+    Archive & ar, 
+    boost::optional<T> & t, 
+    const unsigned int /*version*/
+){
+    bool tflag;
+    ar >> boost::serialization::make_nvp("initialized", tflag);
+    if (tflag){
+        unsigned int v = 0;
+        if(3 < ar.get_library_version()){
+            ar >> boost::serialization::make_nvp("item_version", v);
+        }
+        detail::stack_construct<Archive, T> aux(ar, v);
+        ar >> boost::serialization::make_nvp("value", aux.reference());
+        t.reset(aux.reference());
+    }
+    else {
+        t.reset();
+    }
+}
+
+template<class Archive, class T>
+void serialize(
+    Archive & ar, 
+    boost::optional<T> & t, 
+    const unsigned int version
+){
+    boost::serialization::split_free(ar, t, version);
+}
+
+// the following would be slightly more efficient.  But it
+// would mean that archives created with programs that support
+// TPS wouldn't be readable by programs that don't support TPS.
+// Hence we decline to support this otherwise convenient optimization.
+//#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
+#if 0
+
+template <class T>
+struct implementation_level<optional<T> >
+{
+    typedef mpl::integral_c_tag tag;
+    typedef mpl::int_<boost::serialization::object_serializable> type;
+    BOOST_STATIC_CONSTANT(
+        int , 
+        value = boost::serialization::implementation_level::type::value
+    );
+};
+
+template<class T>
+struct tracking_level<optional<T> >
+{
+    typedef mpl::integral_c_tag tag;
+    typedef mpl::int_<boost::serialization::track_never> type;
+    BOOST_STATIC_CONSTANT(
+        int , 
+        value = boost::serialization::tracking_level::type::value
+    );
+};
+
+#endif
+
+} // serialization
+} // namespace boost
+
+#endif // BOOST_SERIALIZATION_OPTIONAL_HPP_