Re: [Boost-users] Boost.Serialization: Restoringobjectstate(preventcreation of a new object)?

31 Aug 2010

      Robert Ramey wrote:
...
ray@maya-studio.com wrote:
...
...
That's likely something else entirely.  We'd have to see more code.
Forget my previous post, the exception was due to mixed up ofstream
and ifstream...
Just to resume - if I have a list of pointers to the objects (all
derived from the same base class) and I'd like to serialize them
through a reference, a code like this would be needed:
// List of pointers
A a;
B b; // Derived from A
C c; // Derived from C
std::list list;
list.push_back(&a);  // Base
list.push_back(&b);  // Derived
list.push_back(&c);  // Derived
...
// Save
std::ofstream ofs("c:/test.xml");
boost::archive::xml_oarchive oa(ofs);
BOOST_FOREACH(A* pA, list)
{
     if (dynamic_cast(pA))
     {
          B& b = *static_cast(pA);
          oa & BOOST_SERIALIZATION_NVP(b);
     }
     else if (dynamic_cast(pA))
     {
          C& c = *pA;
          BOOST_SERIALIZATION_NVP(c);
     }
     else
     {
          A& a = *pA;
          BOOST_SERIALIZATION_NVP(a);
     }
}
Am I right?
It's not absolutely clear what your object here is.
But the following would be equivalent to the above as far as I can
tell - and a lot simpler
// Save
std::ofstream ofs("c:/test.xml");
boost::archive::xml_oarchive oa(ofs);
oa << list;
whoops, I missed the part about skipping the pointer part.

So I guess your  method above would work  - though I'd have to think about 
it.

of course if you had

std::list list;

there would be nothing to do.

Robert Ramey