Overloading Class Member Function - c++

Question

I have overloaded a function fn as fn(int,char) & fn(int&,char&) as shown below:
#include <iostream>
using namespace std;
void fn(int a, char c);
void fn(int& a, char& c);
int main()
{
int a=10;
char c= 'c';
cout << "Inside main()" << endl;
cout << hex << "&a : " << &a << endl;
cout << hex << "&c : " << (int *)&c << endl;
static_cast<void(*) (int&, char&)> (fn)(a, c);
return 0;
}
void fn(int a, char c)
{
int tempInt;
char tempChar;
cout << "\n\nInside Call By Value Function " << endl;
cout << hex << "&a : " << &a << endl;
cout << hex << "&c : " << (int *)&c << endl;
cout << hex << "&tempInt : " << &tempInt << endl;
cout << hex << "&tempChar : " << (int *)&tempChar << endl;
}
void fn(int& a, char& c)
{
cout << "\n\nInside Call By Reference Function " << endl;
cout << hex << "*a : " << &a << endl;
cout << hex << "*c : " << (int*) &c << endl;
}
The resolution for call to fn(int,char) or fn(int&,char&) is made through cast static_cast<void(*) (int&, char&)> (fn)(a, c);
It gives output:
$ ./Overloading
Inside main()
&a : 0x22ac5c
&c : 0x22ac5b
Inside Call By Reference Function
*a : 0x22ac5c
*c : 0x22ac5b
Now when I put this in a class as below:
#include <iostream>
using namespace std;
class Test{
public:
void fn(int a, char c);
void fn(int& a, char& c);
};
int main()
{
int a=10;
char c= 'c';
Test T();
cout << "Inside main()" << endl;
cout << hex << "&a : " << &a << endl;
cout << hex << "&c : " << (int *)&c << endl;
static_cast<void(*) (int&, char&)> (T.fn)(a, c);
return 0;
}
void Test::fn(int a, char c)
{
int tempInt;
char tempChar;
cout << "\n\nInside Call By Value Function " << endl;
cout << hex << "&a : " << &a << endl;
cout << hex << "&c : " << (int *)&c << endl;
cout << hex << "&tempInt : " << &tempInt << endl;
cout << hex << "&tempChar : " << (int *)&tempChar << endl;
}
void Test::fn(int& a, char& c)
{
cout << "\n\nInside Call By Reference Function " << endl;
cout << hex << "*a : " << &a << endl;
cout << hex << "*c : " << (int*) &c << endl;
}
I get below error:
$ g++ -Wall Overloading.cpp -o Overloading
Overloading.cpp: In function ‘int main()’:
Overloading.cpp:23:42: error: request for member ‘fn’ in ‘T’, which is of non-class type ‘Test()’
How do I resolve this?
How to make a proper call for T's fn(int&,char&)
I guess in my code the expression static_cast<void(*) (int&, char&)> (T.fn)(a, c); is incorrect.
Please help.
Thanks
EDIT:
My mistake
editing Test T() to Test T;
gives error
$ g++ -Wall Overloading.cpp -o Overloading
Overloading.cpp: In function ‘int main()’:
Overloading.cpp:23:44: error: invalid static_cast from type ‘<unresolved overloaded function type>’ to type ‘void (*)(int&, char&)’

Answer 1

First: T is no variable, T is function, that returns Test and receive nothing.
Second: function-pointer is not member-function-pointer. You should use this syntax
typedef void (Test::*function)(int&, char&);
function f = &Test::fn;
(T.*f)(a, c);

Answer 2

See error: request for member '..' in '..' which is of non-class type: the problem is with Test T();, try ommiting the parentheses.

Answer 3

When you do Test T();, you're saying that T is a function with return type Test. However no such thing exists in your code.
The solution is:
Test T;