Hi,

I want to use boost serialization to serialize a boost function. In other places I learned that I need to use non-intrusive serialization and the target<>() method, but I still don’t get it to work:

#include <vector>

#include <iostream>

#include <fstream>

#include <boost/archive/text_oarchive.hpp>

#include <boost/archive/text_iarchive.hpp>

#include <boost/function.hpp>

class A {

    public:

    void func1() {

        std::cout << "Hello World";

    }

};

typedef void (A::*fPointerType)();

class FuncPointerWrapper {

    boost::function<void (A*)> f;

    friend class boost::serialization::access;

    template<typename Archive>void serialize(Archive & ar, const unsigned int version) {

        ar & f;

    }

public:

    FuncPointerWrapper() {}

    FuncPointerWrapper(fPointerType fun) { f = fun; }

    boost::function<void (A*)> getFuncPointer() {return f;}

};

//non-intrusive

namespace boost { namespace serialization {

        template<typename Archive>void serialize(Archive & ar,boost::function<void (A*)> & f, const unsigned int version) {

           ar & (f.template target<fPointerType>());

                //error: no match for 'operator&' in 'ar & ((boost::function_base*)(+f))->boost::function_base::target [with Functor = void (A::*)()]()'|

                // but how do I have to use it then?

        }

    }

}

int main() {

    FuncPointerWrapper fpw(&A::func1);

    std::ofstream ofs("filename");

    {

        boost::archive::text_oarchive oa(ofs);

        // write class instance to archive

        oa << fpw;

                // archive and stream closed when destructors are called

    }

    A a;

    fpw.getFuncPointer()(&a);

    // Some other place, some other time:

    FuncPointerWrapper fpw2;

    {

        std::ifstream ifs("filename");

        boost::archive::text_iarchive ia(ifs);

        ia >> fpw2;

    }

    A b;

    fpw2.getFuncPointer()(&b);

}