None
    }
    fn as_datum(&self) -> Option<&dyn PrimitiveDatum> {

/// SOmething that acts like a structure when used as a VM Primitive
pub trait PrimitiveStruct: PrimitiveData {}

/// Something that has a canonical datum representation
pub trait PrimitiveDatum: PrimitiveData {}

        write!(
            f,
            "#<{}>",
            self.inner
                .as_debug()
                .map(|d| format!("{:?}", d))
                .unwrap_or_else(|| format!("primitive {}", self.inner.type_name()))
        )

        if let Some(datum) = self.as_datum() {
            _ = datum;
            // The debug representation is the print of the datum
            todo!()
        } else {
            write!(
                f,
                "#<{}>",
                self.inner
                    .as_debug()
                    .map(|d| format!("{:?}", d))
                    .unwrap_or_else(|| format!("primitive {}", self.inner.type_name()))
            )
        }

// TODO Change Debug to output datum representation

// TODO Change Debug to output datum representation
// Null -> ()
// Leaf(prim) -> <Debug of prim>
// Cons(car, cdr) -> (<Debug of car> <spliced Debug of cdr>)
// We might have a special "DebugCdr" struct just to handle the debug printing of cdr
// We will *definitely* need a helper "CycleIter" that can iterate through (possibly)
// cyclical datstructures

// TODO handle ports (they must be able to write/read from garbage-collected bytevectors)