My method disappeared!!

What happends here, and how do i get around it?

Code:

---

class Base
{
public:
        int foo(int, int)
        {
                //implemented
        }
        virtual int foo(int) = 0;
};

class Concrete: public Base
{
public:
        virtual int foo(int)
        {
                //implemented
        }
};

---

Creating a Concrete object my compiler does not resolve the
foo(int,int) method.
I get the following error using VS.net 2003.

Code:

---

foo' : function does not take 2 arguments

---

I guess i could solve it doing something like

Code:

---

class Base
{
public:
        virtual int foo(int, int)
        {
                //implemented
        }
        virtual int foo(int) = 0;
};

class Concrete: public Base
{
public:
        virtual int foo(int)
        {
                //implemented
        }
        virtual int foo(int x,int y)
        {
                return Base::foo(x,y);
        }
};

---

But i think that should not be necessary?
Help! :)

That's the way it is. :( A function with the same name as a base function, hides the base function--even if it has a different signature. To overload a function, the functions must be declared in the same scope.

As for the reason, this is from google groups:

Quote:

---

It is to avoid confusion caused by unexpected implicit conversion of
parameter types, causing a call of an unexpected and sometimes unknown
method from the base class. (i.e, if only public class interface is
known, but there are also some unknown, protected methods as well).

---

=(
Thanks for the reply 7stud.

You don't have to write a forwarding function in Derived, you can employ a using declaration in Derived to unhide any version of foo in Base that isn't overridden and bring it into Derived's scope:

using Base::foo;

I found I had to put that as the first line in Derived's public section to get it to work. Check out this discussion:

http://groups.google.com/group/comp....&start=2&num=3

Arrrgh! I had my Base's and Derived's mixed up, so I had to edit my previous post.

Aah, that discussion thread cleared it up.
Cheers.