Re: dynamic function definition

I need to define the body of a function in the constructor of
a class. For example, the class has a member function Log
(that is the public interface of the class), but I want the
body of this function to be defined as something or as
something else in the constructor of the class:

class MyClass
{
public:
    void Log(const int& id, const int& value);
private:
    void LogON(const int& id, const int& value);
    void LogOFF();

};

MyClass::MyClass
{
    // define here whether the function "Log" will behave as LogON or
LogOFF according to a switch
}

void MyClass::LogON(const int& id, const int& value)
{
    // do something like push_back
}

void MyClass::LogOFF()
{
    // do nothing
}

// don't know if I need or not the following definition
void MyClass::Log(const int& id, const int& value)
{
}

Any suggestion on how to do this?