Function pointer to member function

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The syntax is wrong. A member pointer is a different type category from a ordinary pointer. The member pointer will have to be used together with an object of its class:

class A {
public:
 int f();
 int (A::*x)(); // <- declare by saying what class it is a pointer to
};

int A::f() {
 return 1;
}


int main() {
 A a;
 a.x = &A::f; // use the :: syntax
 printf("%d\n",(a.*(a.x))()); // use together with an object of its class
}

a.x does not yet say on what object the function is to be called on. It just says that you want to use the pointer stored in the object a. Prepending a another time as the left operand to the .* operator will tell the compiler on what object to call the function on.

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