Question

I have a super class like this:

class Parent
{
public:
    virtual void Function(int param);
};

void Parent::Function(int param)
{
    std::cout << param << std::endl;
}

..and a sub-class like this:

class Child : public Parent
{
public:
    void Function(int param);
};

void Child::Function(int param)
{
    ;//Do nothing
}

When I compile the sub-class .cpp file, I get this error

warning C4100: 'param' : unreferenced formal parameter

As a practice, we used to treat warnings as errors. How to avoid the above warning?

Thanks.

Answer 1

In C++ you don’t have to give a parameter that you aren’t using a name so you can just do this:

void Child::Function(int)
{
    //Do nothing
}

You may wish to keep the parameter name in the declaration in the header file by way of documentation, though. The empty statement (;) is also unnecessary.