/// However the pointer may still dangle if it isn't dereferenced.
///
/// Unlike `*mut T`, `Unique<T>` is covariant over `T`. This should always be correct
/// for any type which upholds Unique's aliasing requirements.
#[unstable(
feature = "ptr_internals",
issue = "none",
reason = "use `NonNull` instead and consider `PhantomData<T>` \
(if you also use `#[may_dangle]`), `Send`, and/or `Sync`"
)]
#[doc(hidden)]
#[repr(transparent)]
#[rustc_layout_scalar_valid_range_start(1)]
pub struct Unique<T: ?Sized> {
pointer: *const T,
// NOTE: this marker has no consequences for variance, but is necessary
// for dropck to understand that we logically own a `T`.
//
// For details, see:
// https://github.com/rust-lang/rfcs/blob/master/text/0769-sound-generic-drop.md#phantom-data
_marker: PhantomData<T>,
Heh, that's a rustdoc bug: I guess it fails to realize that Unique is hidden when it happens cross-crate (cc @jyn514 @GuillaumeGomez , does that seem plausible?)
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