[Boost-users] boost serialization & module boundaries

From: Christian Widmer (cwidmer_at_[hidden])
Date: 2008-02-27 11:04:58

Hi,

I'm trying to use boost to serialize a machine learning library that I'm
working with. It all worked out very conveniently, but it seems now,
that I have hit a dead end. I've been looking on the net but couldn't
find any information that worked for me, so here we go:

The problem is, that the library consists of several modules, which are
dynamically linked. For instance the class KernelMachine has a field
kernel of type Kernel, which is contained in a separate module (in the
sense of a shared object).

The following code compiles, but when I try to serialize a
CKernelMachine object I get an "unregistered_class" error. (CKernel does
serialize fine, when called directly)

    class CKernelMachine : public CClassifier
    {

      private:

        friend class boost::serialization::access;
        template<class Archive>
        void serialize(Archive & ar, const unsigned int version)
        {
          ar & boost::serialization::base_object<CClassifier>(*this);

          ar.register_type(static_cast<CGaussianKernel *>(NULL));
          ar & kernel;

          std::cout << "done CKernelMachine" << std::endl;
        }

        protected:
      CKernel* kernel;
    };

I found some threads that pointed me towards BOOST_CLASS_EXPORT, but I'm
not exactly sure how to use it.

So my question is - is it in principle even possible to serialize across
module (shared-object) boundaries.

If so, how should I go about? Any pointers would be greatly appreciated.

- Chris