Storing a list of arbitrary objects in C++

Question

In Java, you can have a List of Objects. You can add objects of multiple types, then retrieve them, check their type, and perform the appropriate action for that type.
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Answer 1

C++ does not support heterogenous containers.

If you are not going to use boost the hack is to create a dummy class and have all the different classes derive from this dummy class. Create a container of your choice to hold dummy class objects and you are ready to go.

class Dummy {
   virtual void whoami() = 0;
};

class Lizard : public Dummy {
   virtual void whoami() { std::cout << "I'm a lizard!\n"; }
};


class Transporter : public Dummy {
   virtual void whoami() { std::cout << "I'm Jason Statham!\n"; }
};

int main() {
   std::list hateList;
   hateList.insert(new Transporter());
   hateList.insert(new Lizard());

   std::for_each(hateList.begin(), hateList.end(), 
                 std::mem_fun(&Dummy::whoami));
   // yes, I'm leaking memory, but that's besides the point
}

If you are going to use boost you can try boost::any. Here is an example of using boost::any.

You may find this excellent article by two leading C++ experts of interest.

Now, boost::variant is another thing to look out for as j_random_hacker mentioned. So, here's a comparison to get a fair idea of what to use.

With a boost::variant the code above would look something like this:

class Lizard {
   void whoami() { std::cout << "I'm a lizard!\n"; }
};

class Transporter {
   void whoami() { std::cout << "I'm Jason Statham!\n"; }
};

int main() {

   std::vector< boost::variant > hateList;

   hateList.push_back(Lizard());
   hateList.push_back(Transporter());

   std::for_each(hateList.begin(), hateList.end(), std::mem_fun(&Dummy::whoami));
}