[Boost-users] [serialization] default constructor problem

From: Andreas Sæbjørnsen (andreas.saebjoernsen_at_[hidden])
Date: 2006-01-13 21:20:27

Hi,
I am currently experimenting with writing a compiler tool which generates
the code necessary for using boost::serialization. While working on this I
found that I am unable to serialize a variable declaration which is a
reference to a class constructed with the default constructor '()'( ex.
class foo var(); ). I have tried to find an explanation for this in the
examples, documentation and through searching the web without success. Using
pointers it works fine with the
default constructor and I do not see why it should be any different for
references (as references in essence are pointers). Is it possible to
serialize a class constructed using the default constructor using
boost::serialization, and if so how?

Example:
#include <fstream>

// include headers that implement a archive in simple text format
#include <boost/archive/text_oarchive.hpp>
#include <boost/archive/text_iarchive.hpp>

class gps_set
{
  friend class boost::serialization::access;

  public:
     int x;
     gps_set::gps_set(){ x = 2;};
     virtual gps_set::~gps_set(){};
     gps_set::gps_set(int i) : x(1) {};

  private:
     template<typename Archive>
     void serialize(Archive& ar, const unsigned int version){
               ar& x;
     }// End method: X::serialization
};
int main()
{
    // save the schedule
     std::ofstream ofs("filename");

    // create class instance
    //Compile time error if s1() is used. No error if s1(1) is used.
     const gps_set s1();
    // save data to archive
    {
      boost::archive::text_oarchive oa(ofs);
        // write class instance to archive
        oa << s1;
        // archive and stream closed when destructors are called
    }
};

Thanks,
Andreas Saebjoernsen