Can Static Functions Be Virtual in C++?
In C++, a static member function of a class cannot be virtual. Virtual functions are invoked when you have a pointer or reference to an instance of a class. Static functions aren't tied to the instance of a class but they are tied to the class. C++ doesn't have pointers-to-class, so there is no scenario in which you could invoke a static function virtually.
For example, below program gives compilation error,
// CPP Program to demonstrate Virtual member functions
// cannot be static
#include <iostream>
using namespace std;
class Test {
public:
virtual static void fun() {}
};
Output
prog.cpp:9:29: error: member ‘fun’ cannot be declared both virtual and static
virtual static void fun() {}
^
Also, static member function cannot be const and volatile. Following code also fails in compilation,
// CPP Program to demonstrate Static member function cannot
// be const
#include <iostream>
using namespace std;
class Test {
public:
static void fun() const {}
};
Output
prog.cpp:8:23: error: static member function ‘static void Test::fun()’ cannot have cv-qualifier
static void fun() const {}
^