Heterogeneous container

[Chris_F]

Actually, that may not be necessary.

There is Boost.PropertyTree that has basically that exact interface, and furthermore, it already works with the serializer!

boost::property_tree::ptree pt;
pt.put<std::string>("name", "Chris");
pt.put("age", 23);
std::ofstream ofs("out.xml");
boost::archive::xml_oarchive xml(ofs);
xml << BOOST_SERIALIZATION_NVP(pt);