Request: Please provide an example that packs and unpacks a derived class

[quazar0]

Could you please add an example that will pack and unpack a derived class, similar to this class C (which is derived from class P).
And include the proper pack() method in each class.

class C: public P
{
public:
   string sName;

   template< class T >
   void pack( T &pack ) {
      pack( sName, ??? );
   }

}

class P
{
public:
   int uid;

   template< class T >
   void pack( T &pack ) {
      pack( uid );
   }
}

And maybe more importantly, the example should include an example where class C is derived from a std class (e.g. std::map).

Thank you.