They don't own anything. It's just a pointer and length. They don't allocate/deallocate.

I mean clearly something needs to own the buffer for a new string.

Sure, but that's not the string_view's problem, you can't just make string_views, the string you want to borrow a view into needs to exist first.

Imagine you go to a library and insist on borrowing "My Cousin Rachel", but they don't have it. "Oh I don't care whether you have the book, I just want to borrow it" is clearly nonsense. If they don't have it, you can't borrow it.

Walter is talking about D, and he said this:

> D doesn't distinguish between a string and a string view.

In C++ std::string owns the buffer and std::string_view borrows it. If there is no difference between the two in D, then how is this difference bridged?

You can use automatic memory management and not worry about it. Or you can use D's prototype ownership/borrowing system. Or you can encapsulate them in something that manages the memory. Or you can do ownership/borrowing by convention (it's not hard to do).

Automatic memory management makes copies?

No. Another word for automatic memory management is garbage collection.

I guess I should rephrase. Let's say I have a string, which owns its buffer. What happens in D if I take a substring of it? Does a copy of that section occur to form a new string?