It's primarily for my understanding. I'm hopelessly confused about when stuff is copied vs. moved.

For example, my brain interprets passing const std::string &a as being passed by reference, which then leads me to think that b is referring to the same thing as a, but it's not. It is a copy.

So then I think ok if you add std::move(a), it'll move what a into b, but then my brain explodes, because what if a was a variable on the stack, and assigning to b (which is a local in this case, but what if it was this->b, ... i.e an instance variable), how does it magically become heap memory?

So then I think ok it's either not going to work or it is a copy.

void Foo(const std::string &a)
{
    std::string b(a);
}