Boost Serialization unordered_multimap

Hi.
How can I serialize an unordered_multimap with boost.Serialization library? I have tried this:

Code:

---

namespace boost {
namespace serialization {


template<class Archive, typename X, typename Y>
void load(Archive & ar, boost::unordered_multimap<X,Y> & g, const unsigned int version)
{

    std::size_t size;
    ar & size;
    while(size--)
    {
        std::pair<X,Y> m;
        ar & m;
        g.insert(m);
    }
}
template<class Archive, typename X, typename Y>
void save(Archive & ar, const boost::unordered_multimap<X,Y> & g, const unsigned int version)
{
    std::size_t size = g.size();
    ar & size;
    for(boost::unordered_multimap<X,Y>::iterator it = g.begin(); it != g.end(); ++it)
    {
        ar & (*it);
    }
}

}
}

---

But it didn't work. The compiler complains about a serialize method is missing in boost::unordered_multimap but as I know should it work if I define a save and load function in the serialization namespace, but it doesn't.

Any clue what I am doing wrong?

Thanks in advance.

My solution:

Code:

---

namespace boost
{
    namespace serialization
    {
        template<class Archive, class Key, class Mapped, class Hash, class Pred, class Alloc >
        inline void save(Archive & ar, const boost::unordered_multimap<Key, Mapped, Hash, Pred, Alloc> &t, const unsigned int)
        {
            boost::serialization::stl::save_collection<Archive, boost::unordered_multimap<Key, Mapped, Hash, Pred, Alloc> >(ar, t);
        }

        template<class Archive, class Key, class Mapped, class Hash, class Pred, class Alloc >
        inline void load(Archive & ar, boost::unordered_multimap<Key, Mapped, Hash, Pred, Alloc> &t, const unsigned int)
        {
            boost::serialization::stl::load_collection<Archive, boost::unordered_multimap<Key, Mapped, Hash, Pred, Alloc>,
            boost::serialization::stl::archive_input_multimap<Archive, boost::unordered_multimap<Key, Mapped, Hash, Pred, Alloc> >,
            boost::serialization::stl::no_reserve_imp< boost::unordered_multimap<Key, Mapped, Hash, Pred, Alloc> > >(ar, t);
        }

        // split non-intrusive serialization function member into separate
        // non intrusive save/load member functions
        template<class Archive, class Key, class Mapped, class Hash, class Pred, class Alloc >
        inline void serialize(Archive & ar, boost::unordered_multimap<Key, Mapped, Hash, Pred, Alloc> &t, const unsigned int file_version)
        {
            boost::serialization::split_free(ar, t, file_version);
        }
    }
}

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