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> + > +impl Refcount { > + /// Construct a new [`Refcount`] from an initial value. > + /// > + /// The initial value should be non-saturated. > + #[inline] > + pub fn new(value: i32) -> Self { > + build_assert!(value >=3D 0, "initial value saturated"); Given that `inc` will WARN if the refcount is `0`, do we want to accept `0` here?