Non-const copy constructor and implicit conversions on return value

Question

Consider the following C++ code:

struct B { };
struct A
{
        A(int);
        A(A&); // missing const is intentional
        A(B);
        operator B         


        

Answer 1

The error lists all the potential candidates to be used, and why they cannot be used. It lists the conversion from B because its one of the constructors, but it doesn't know how to use it in this case, so it doesn't.