message: Add more features on the NoneOr type
  Summary: Useful utilities.
diff: @@ -68,7 +68,7 @@ impl AllocFrozenValue for NoneType {
  }
  /// Equivalent of a Rust [`Option`], where [`None`] is encoded as [`NoneType`]. Useful for its [`UnpackValue`] instance.
  -#[derive(Debug)]
  +#[derive(Debug, Eq, PartialEq)]
  pub enum NoneOr<T> {
  None,
  Other(T),
  @@ -82,6 +82,11 @@ impl<T> NoneOr<T> {
  Self::Other(x) => Some(x),
  }
  }
  +
  + /// Is the value a [`NoneOr::None`].
  + pub fn is_none(&self) -> bool {
  + matches!(self, NoneOr::None)
  + }
  }
  impl<'v, T: UnpackValue<'v>> UnpackValue<'v> for NoneOr<T> {
  