I'm having problems wrapping my head around this. I have a function

void foo(istream& input) {
     input = cin;
}

This fails (I'm assuming because cin isn't supposed to be "copyable".

however, this works

void foo(istream& input) {
    istream& baz = cin;
}

Is there a reason that I can get a reference to cin in baz but I cannot assign it to input?

Thanks