c++ - Function pointer to member function -

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i'd set function pointer member of class pointer function in same class. reasons why i'm doing complicated.

in example, output "1"

class { public:  int f();  int (*x)(); }  int a::f() {  return 1; }   int main() {  a;  a.x = a.f;  printf("%d\n",a.x()) }

but fails @ compiling. why?

the syntax wrong. member pointer different type category ordinary pointer. member pointer have used object of class:

class { public:  int f();  int (a::*x)(); // <- declare saying class pointer };  int a::f() {  return 1; }   int main() {  a;  a.x = &a::f; // use :: syntax  printf("%d\n",(a.*(a.x))()); // use object of class }

a.x not yet on object function called on. says want use pointer stored in object a. prepending a time left operand .* operator tell compiler on object call function on.


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