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

Because you cannot do more than one implicit conversion. You would have to go A::A(A::A(int)::operator B()) to make that work, and that's way too many steps for the compiler to figure out on it's own.