“Option” is the operative word. A type that does not implement the correct trait cannot be used in a way that requires the trait. If you are writing anything no

“Option” is the operative word. A type that does not implement the correct trait cannot be used in a way that requires the trait. If you are writing anything non-trivial that would probably be preferable. It requires nothing, that is the default behavior, so I did not bother to mention it.