Forward Declaration of Class, Function

Question

When forward declarations of functions work in a source file (.cpp), why would the same doesn\'t work for classes ?

Thanks.

// main.cpp

void forwar         


        

Answer 1

when you create 2 class & one function can access data from on class to another class then it is a friend function

forword declaration is use to know which class in next

class abc;

class xyz

{

data member;

public:

friend void getdata();

other member function

}

class abc

{

data member

public:

friend void getdata();

}