How should we implement Valuable for Uuid? about valuable

[KodrAus]

On the one hand it seems like we could actually implement Valuable in terms of the underlying bytes as Listable, and also implement Displayable, except for these constraints on the subtypes of Valuable:

Values that implement Listable must return Value::Listable from their Valuable::as_value implementation.

It almost seems like something like this on the Valuable trait might make it possible to advertise multiple representations:

pub trait Valuable {
    fn as_value(&self) -> Value;

    // default impl that can be overridden
    fn as_listable(&self) -> Option<&dyn Listable> {
        self.as_value().as_listable()
    }

    ..
}

And remove the single subtrait constraint, supporting a default, and then any number of specialized alternative representations. That constraint might be there for a good reason though.

[hawkw]

On the one hand it seems like we could actually implement Valuable in terms of the underlying bytes as Listable,

This also makes me wonder a bit if there should be some kind of "ByteArrayable" primitive...

[KodrAus]

A &[u8] variant for Value seems reasonable to me, depending on how purely structural you're wanting to keep the Value enum. It does potentially mean someone looking for an array of bytes might need to consider both the Bytes and the Listable variants unless you require that values should produce the most specific variant possible (so a value that doesn't produce a Bytes variant is at fault and needs to be fixed). That would make it harder to add new specific variants in a semantically backwards-compatible way though 🤔