[Solved] C++ inheritance question

I have a base class and a bunch of inherited classes.
I am doing something like this in the main.
baseclass* base[2];
base[0]= new _derived1("hello");
base[1]= new _derived2("world");
How do I code my base class or what-ever-else so that I CAN'T do this:
baseclass* base2;
base2 = new baseclass("class");
The base class has 1 constructor with an argument type string. I can't have a default constructor.
So in short. I can create a particular derived class, like a derived1, but can't create a plain base class. (it should throw a compilation error)
Any help would be appreciated.
Thanks.
Last edited by lamdacore (2011-02-06 00:38:43)

Oh I want a compile error when I do this:
baseclass* base2;
base2 = new baseclass("class");
Example code. So I don't want the base class to be able to make a Base type object. As soon as I do that it SHOULD throw a compilation error.
class Base{
public:
Base(string st):m_st(st)
virtual ~Base(){
virtual string ann() const{
return "";
virtual string bnn() const{
return m_st;
virtual string cnn(string msg) const{
string k="hey ";
k.append(msg);
return k;
private:
string m_st;
class derived1:public Base{
public:
derived1(string st):Base(st){
virtual ~derived1(){
cout<<"kill";
virtual string ann() const{
return "hullo";
virtual string bnn() const{
return Base::bnn();
virtual string cnn(string msg) const{
string k="hey ";
k.append(msg);
return k;
private:
string m_st;
Last edited by lamdacore (2011-02-06 23:38:23)

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