Trouble with inheritance.....

Hi all,

I'm writing a program which uses inheritance but it won't compile! I believe the constructor of the base class is to blame, but I'm not sure as I've not had much experience with inheritance.

Please find 5 of my code files attached ( 5 is maximum allowed ) and the last 2 below for perusal.

Code:

// userControlledCharacterClass.h
#ifndef USERCONTROLLEDCHARACTERCLASS_H
#define USERCONTROLLEDCHARACTERCLASS_H
#include "RPG.h"


class userControlledCharacterClass: public RPG
{
public:
    userControlledCharacterClass(); // constructor
    userControlledCharacterClass( string, string, int, int, int, int ); // constructor
    ~userControlledCharacterClass(); // destructor
protected:
private:
};

#endif // USERCONTROLLEDCHARACTERCLASS_H

Code:

// userControlledCharacterClass.cpp
#include "userControlledCharacterClass.h"
using namespace std;

userControlledCharacterClass::userControlledCharacterClass()
{

} // end constructor userControlledCharacterClass

userControlledCharacterClass::userControlledCharacterClass( string a, string b, int c, int d, int e, int f )
{
    setName( a );
    setDescription( b );
    setXP( c );
    setHP( d );
    setAP( e );
    setLocation( f );
} // end constructor userControlledCharacterClass

userControlledCharacterClass::~userControlledCharacterClass()
{
    cout << getName() << " has died!1" << endl;
} // end destructor ~userControlledCharacterClass()

Originally Posted by JM1082

I'm writing a program which uses inheritance but it won't compile!

What is the exact error message, and where is it detected?

Detected in line: 5 & 10 of userControlledCharacterClass.cpp
Error message reads: Undefined reference to RPG::RPG()

Strangely, this error is detected twice at each line.....

You forgot to define the default constructor for RPG.

Thanks Laserlight! Your sharp eye is only exceed by your majesty!

However, I've two last questions!

Is it compulsory to include a constructor with an empty arguments list?

And, why are seven objects of each class destroyed when I've only created three?

Originally Posted by JM1082

Is it compulsory to include a constructor with an empty arguments list?

No. However, if you do not have a default constructor for a base class, then the constructors of classes that derive from the base class would need to specify which base class constructor to invoke in their initialiser lists.

Originally Posted by JM1082

And, why are seven objects of each class destroyed when I've only created three?

Maybe you did not notice that you were doing some copying.

Off topic: I just heard that Barbara Liskov, after whom the Liskov substitution principle is named, is in Singapore right now giving a talk at my alma mater. Pity I am unable to attend.