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Calling the global constructor function
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Calling the global constructor function
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I have this code:
#include <iostream>
using namespace std;
struct A;
struct B;
void g(A* a){ cout << "A";}
void g(B* b){ cout << "B";}
struct A{
A(){ g(this); }
};
struct B : A{
B(){}
};
int main() {
B* b=new B();
return 0;
}
in which the output is :
Does this mean the type of this pointer passed to constructor A() is of type A*?
The thing is a B object is also a A object. While you are inside of the functions of A the class does not know if it is a B or not. So the this-ptr will be of type A*.
When you are calling functions inside of B it is B*.
Tags
oop
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