fn mk_cycle<Qcx, V, R>(
    qcx: Qcx,
    cycle_error: CycleError,
    handler: HandleCycleError,
    cache: &dyn QueryStorage<Value = V, Stored = R>
) -> Rwhere
    Qcx: QueryContext,
    V: Debug + Value<Qcx::DepContext>,
    R: Clone,