Template for a deposit

[dkaip]

How i can make a prototype for a function for all stuff?
I have the code from SneakySnake ...

#include <iostream>
#include <string>
#include <vector>

using namespace std;

struct Cat
{
    string name;
    int age;
};

struct Pencil
{
    float sharpness;
    float length;
};

struct ListOfThings
{
    enum Type
    {
        CatList,
        PencilList
    } type;
    void *listData;
};

vector<Pencil> pencils;
vector<Cat> cats;
vector<ListOfThings> myThings;

int main()
{
    cats.push_back( {"Joey", 4});
    cats.push_back( {"Mitzi", 6});
    cats.push_back( {"Garfield", 10});
    pencils.push_back( {1.0f, 17.6f});
    pencils.push_back( {0.6f, 12.1f});
    pencils.push_back( {1.6f, 24.6f});
    pencils.push_back( {0.2f, 18.0f});
    myThings.push_back( {ListOfThings::CatList, &cats});
    myThings.push_back( {ListOfThings::PencilList, &pencils});
    cout << "Hey look, I just found the lists of the things I own. I made them a while ago. Let's take a look at them!\n\n";
    for (const ListOfThings& list : myThings)
    {
        if (list.type == ListOfThings::CatList)
        {
            cout << "Ahh... A list of cats... curious...\n";
            for (const Cat& cat : *static_cast<vector<Cat>*>(list.listData))
                cout << cat.name << ", age: " << cat.age << '\n';
        }
        else if (list.type == ListOfThings::PencilList)
        {
            cout << "Hmm... A bunch of pencils...\n";
            for (const Pencil& pencil : *static_cast<vector<Pencil>*>(list.listData))
            {
                cout << "sharpness: " << pencil.sharpness << ", length: " << pencil.length << '\n';
            }
        }
    }
}

and i must make a template to construct a function like ...

template <typename T>
void exportObjects(ListOfThings::T){ // here is error ...
    for (const ListOfThings& list : all)
    {
        if (list.type == ListOfThings::T)
        {
            vector<T>a = *static_cast<vector<T>*>(list.listData);
            vector<T>::iterator it=a.begin();
            for (const T& i : *static_cast<vector<T>*>(list.listData))
            {
        //        how i can access ?...
            }
        }
    }
}