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/// A type used to mark that a struct owns the object(s) it contains,
/// so it has the sole references to them.
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
pub enum Owned {}

/// A type used to mark that the object(s) a struct contains are shared,
/// so there may be other references to them.
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
pub enum Shared {}

mod private {
    pub trait Sealed {}

    impl Sealed for super::Owned {}
    impl Sealed for super::Shared {}
}

/// A type that marks what type of ownership a struct has over the object(s)
/// it contains; specifically, either [`Owned`] or [`Shared`].
///
/// This trait is sealed and not meant to be implemented outside of the this
/// crate.
pub trait Ownership: private::Sealed + 'static {}

impl Ownership for Owned {}
impl Ownership for Shared {}