Matrix of pointers using subscription - c++

Question

So a few days ago I asked and received a very good answer in this thread. Assignment and retrieval using subscript and equals operator overloads
Unfortunately my mistake but it was a little to far from my end use scenario, I'm trying to store pointers to the cchar_t class in nucrsesw/ncurses.h This is what I have currently
#include <iostream>
#include <vector>
#include <string>
#include <ncursesw/ncurses.h>
#include <ncursesw/panel.h>
class Matrix {
std::vector<std::vector<cchar_t*>> m;
public:
Matrix(int x = 0, int y = 0) {
m.resize(x);
for (int i = 0; i < x; ++i)
m[i].resize(y);
}
class Proxy {
std::vector<cchar_t*> &mm;
public:
Proxy(std::vector<cchar_t*> &c) : mm(c) {}
cchar_t& operator[](int index) {
return *mm[index];
}
};
Proxy operator[](int index) {
return Proxy(m[index]);
}
};
int main() {
wchar_t wR = u'W';
cchar_t *w;
setcchar(w, &wR, 0, COLOR_PAIR(0), NULL);
Matrix m(1, 1);
m[0][0] = *w;
std::cout << typeid(m[1][1]).name() << std::endl;
}
I keep getting invalid initialization of reference type in the second subscript overload function. It may be obvious but CPP is not my primary language. Does anyone know how this can be adapted to store pointers? Thanks in advance.
Note the code is edited to show exactly what happens when it seg faults on me.

Answer 1

mm is a reference to an std::vector which holds objects of type cchar_t* (pointers to cchar_t objects). The subscript operator of std::vector returns a reference to the object at the appropriate index. In your case, that would be a reference to a pointer to cchar_t.
To fix your problem, you can dereference the obtained pointer in the return statement: simply change it to return *mm[index];.