Question

I have this code sample:

class Number 
{ 
  int i;
  public:
    Number(int i1): i(i1) {}
    operator int() const {return i;}
};

What are the implications of removing the const modifier from the casting operator?
Does it affect auto casting, and why?

Answer 1

If the conversion operator is not const, you can’t convert const objects:

const Number n(5);
int x = n; // error: cannot call non-const conversion operator