Add a member in a struct that implements a trait specified

Question

Let's say I have this struct in Rust:

// Trait that allows objects that
// implement it to return themselves
// to the caller.
trait ReturnsSelf {
    fn get_self(self) -> Self {
        self
    }
}

struct Data {
    member: u32
}

How would I go to say that member doesn't have to be a u32 , but should simply implement ReturnsSelf as a trait? And can I also say that member should either implement ReturnsSelf or be a u32 ? Or even both?

Answer 1

You declare a generic with a trait bound:

struct Data<T: RetursSelf> {
    member: T,
}