Re: Help getting to a derived class template given a pointer to a no-template base class
 
On Sep 26, 9:32 pm, chris.kemme...@att.net wrote:
class PacketBase
{
   virtual ~PacketBase() {}
                ...
};
template<typename T>
class Packet : public PacketBase
{
   std::vector<T> Values() { return m_Values; }
   std::vector<T>  m_Values;
              ...
};
class UsePackets
{
   std::vector<PacketBase*> m_Packets;
                 ...
};
... somewhere in the main code...
UsePackets foo;
foo.m_Packets.push_back(new Packet<int>);
foo.m_Packets.push_back(new Packet<short>);
PacketBase* packet = foo.m_Packets.at(1);
packet->Values();  // can't access this function
Would something like this work?
class PacketBase
{
   virtual ~PacketBase() {}
   virtual std::vector<boost::any>& Values() const =0;
               ...
};
template<typename T>
class Packet : public PacketBase
{
    std::vector<boost::any>& Values() const { return m_Values; }
    std::vector<boost::any>  m_Values;
               ...
};
class UsePackets
{
    std::vector<PacketBase*> m_Packets;
                  ...
 };
 ... somewhere in the main code...
UsePackets foo;
foo.m_Packets.push_back(new Packet<int>);
foo.m_Packets.push_back(new Packet<short>);
PacketBase* packet = foo.m_Packets.at(1);
vector<boost::any> woot = packet->Values();  
You may also be able to wrap the vector itself in boost::any but I've
never done anything like that.
Saul
  
  
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