Auto merge of #120626 - Mark-Simulacrum:beta-next, r=Mark-Simulacrum

bors · bors · commit 04ba4521971a · 2024-02-04T02:25:51.000Z
[beta] initial branch of 1.77 https://forge.rust-lang.org/release/process.html#promote-branches-t-3-days-monday r? `@Mark-Simulacrum`
diff --git a/compiler/rustc_feature/src/accepted.rs b/compiler/rustc_feature/src/accepted.rs
@@ -77,7 +77,7 @@ declare_features! (
     /// Allows empty structs and enum variants with braces.
     (accepted, braced_empty_structs, "1.8.0", Some(29720)),
     /// Allows `c"foo"` literals.
-    (accepted, c_str_literals, "CURRENT_RUSTC_VERSION", Some(105723)),
+    (accepted, c_str_literals, "1.77.0", Some(105723)),
     /// Allows `#[cfg_attr(predicate, multiple, attributes, here)]`.
     (accepted, cfg_attr_multi, "1.33.0", Some(54881)),
     /// Allows the use of `#[cfg(doctest)]`, set when rustdoc is collecting doctests.
diff --git a/compiler/rustc_feature/src/removed.rs b/compiler/rustc_feature/src/removed.rs
@@ -33,7 +33,7 @@ declare_features! (
     // -------------------------------------------------------------------------
 
     /// Allows using the `amdgpu-kernel` ABI.
-    (removed, abi_amdgpu_kernel, "CURRENT_RUSTC_VERSION", Some(51575), None),
+    (removed, abi_amdgpu_kernel, "1.77.0", Some(51575), None),
     (removed, advanced_slice_patterns, "1.0.0", Some(62254),
      Some("merged into `#![feature(slice_patterns)]`")),
     (removed, allocator, "1.0.0", None, None),
diff --git a/compiler/rustc_feature/src/unstable.rs b/compiler/rustc_feature/src/unstable.rs
@@ -356,7 +356,7 @@ declare_features! (
     /// Allows `#[track_caller]` on async functions.
     (unstable, async_fn_track_caller, "1.73.0", Some(110011)),
     /// Allows `for await` loops.
-    (unstable, async_for_loop, "CURRENT_RUSTC_VERSION", Some(118898)),
+    (unstable, async_for_loop, "1.77.0", Some(118898)),
     /// Allows builtin # foo() syntax
     (unstable, builtin_syntax, "1.71.0", Some(110680)),
     /// Treat `extern "C"` function as nounwind.
@@ -370,7 +370,7 @@ declare_features! (
     /// Allows the use of `#[cfg(sanitize = "option")]`; set when -Zsanitizer is used.
     (unstable, cfg_sanitize, "1.41.0", Some(39699)),
     /// Allows `cfg(sanitizer_cfi_generalize_pointers)` and `cfg(sanitizer_cfi_normalize_integers)`.
-    (unstable, cfg_sanitizer_cfi, "CURRENT_RUSTC_VERSION", Some(89653)),
+    (unstable, cfg_sanitizer_cfi, "1.77.0", Some(89653)),
     /// Allows `cfg(target_abi = "...")`.
     (unstable, cfg_target_abi, "1.55.0", Some(80970)),
     /// Allows `cfg(target(abi = "..."))`.
@@ -516,7 +516,7 @@ declare_features! (
     (unstable, marker_trait_attr, "1.30.0", Some(29864)),
     /// Allows exhaustive pattern matching on types that contain uninhabited types in cases that are
     /// unambiguously sound.
-    (incomplete, min_exhaustive_patterns, "CURRENT_RUSTC_VERSION", Some(119612)),
+    (incomplete, min_exhaustive_patterns, "1.77.0", Some(119612)),
     /// A minimal, sound subset of specialization intended to be used by the
     /// standard library until the soundness issues with specialization
     /// are fixed.
@@ -552,7 +552,7 @@ declare_features! (
     /// Allows using enums in offset_of!
     (unstable, offset_of_enum, "1.75.0", Some(120141)),
     /// Allows using multiple nested field accesses in offset_of!
-    (unstable, offset_of_nested, "CURRENT_RUSTC_VERSION", Some(120140)),
+    (unstable, offset_of_nested, "1.77.0", Some(120140)),
     /// Allows using `#[optimize(X)]`.
     (unstable, optimize_attribute, "1.34.0", Some(54882)),
     /// Allows macro attributes on expressions, statements and non-inline modules.
diff --git a/library/alloc/src/slice.rs b/library/alloc/src/slice.rs
@@ -51,7 +51,7 @@ pub use core::slice::{from_mut, from_ref};
 pub use core::slice::{from_mut_ptr_range, from_ptr_range};
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::slice::{from_raw_parts, from_raw_parts_mut};
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 pub use core::slice::{ChunkBy, ChunkByMut};
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::slice::{Chunks, Windows};
diff --git a/library/alloc/src/vec/cow.rs b/library/alloc/src/vec/cow.rs
@@ -15,7 +15,7 @@ impl<'a, T: Clone> From<&'a [T]> for Cow<'a, [T]> {
     }
 }
 
-#[stable(feature = "cow_from_array_ref", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "cow_from_array_ref", since = "1.77.0")]
 impl<'a, T: Clone, const N: usize> From<&'a [T; N]> for Cow<'a, [T]> {
     /// Creates a [`Borrowed`] variant of [`Cow`]
     /// from a reference to an array.
diff --git a/library/core/src/array/mod.rs b/library/core/src/array/mod.rs
@@ -576,7 +576,7 @@ impl<T, const N: usize> [T; N] {
     /// // We can still access the original array: it has not been moved.
     /// assert_eq!(strings.len(), 3);
     /// ```
-    #[stable(feature = "array_methods", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "array_methods", since = "1.77.0")]
     pub fn each_ref(&self) -> [&T; N] {
         from_trusted_iterator(self.iter())
     }
@@ -595,7 +595,7 @@ impl<T, const N: usize> [T; N] {
     /// assert_eq!(float_refs, [&mut 0.0, &mut 2.7, &mut -1.0]);
     /// assert_eq!(floats, [0.0, 2.7, -1.0]);
     /// ```
-    #[stable(feature = "array_methods", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "array_methods", since = "1.77.0")]
     pub fn each_mut(&mut self) -> [&mut T; N] {
         from_trusted_iterator(self.iter_mut())
     }
diff --git a/library/core/src/intrinsics.rs b/library/core/src/intrinsics.rs
@@ -947,7 +947,7 @@ extern "rust-intrinsic" {
     /// own, or if it does not enable any significant optimizations.
     ///
     /// This intrinsic does not have a stable counterpart.
-    #[rustc_const_stable(feature = "const_assume", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "const_assume", since = "1.77.0")]
     #[rustc_nounwind]
     pub fn assume(b: bool);
 
diff --git a/library/core/src/mem/mod.rs b/library/core/src/mem/mod.rs
@@ -1394,15 +1394,15 @@ impl<T> SizedTypeProperties for T {}
 /// assert_eq!(mem::offset_of!(Option<&u8>, Some.0), 0);
 /// ```
 #[cfg(not(bootstrap))]
-#[stable(feature = "offset_of", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "offset_of", since = "1.77.0")]
 #[allow_internal_unstable(builtin_syntax, hint_must_use)]
 pub macro offset_of($Container:ty, $($fields:expr)+ $(,)?) {
     // The `{}` is for better error messages
     crate::hint::must_use({builtin # offset_of($Container, $($fields)+)})
 }
 
 #[cfg(bootstrap)]
-#[stable(feature = "offset_of", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "offset_of", since = "1.77.0")]
 #[allow_internal_unstable(builtin_syntax, hint_must_use)]
 #[allow(missing_docs)]
 pub macro offset_of($Container:ty, $($fields:tt).+ $(,)?) {
diff --git a/library/core/src/net/mod.rs b/library/core/src/net/mod.rs
@@ -9,7 +9,7 @@
 //! * [`SocketAddr`] represents socket addresses of either IPv4 or IPv6; [`SocketAddrV4`]
 //!   and [`SocketAddrV6`] are respectively IPv4 and IPv6 socket addresses
 
-#![stable(feature = "ip_in_core", since = "CURRENT_RUSTC_VERSION")]
+#![stable(feature = "ip_in_core", since = "1.77.0")]
 
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use self::ip_addr::{IpAddr, Ipv4Addr, Ipv6Addr, Ipv6MulticastScope};
diff --git a/library/core/src/ops/range.rs b/library/core/src/ops/range.rs
@@ -726,7 +726,7 @@ impl<T> Bound<T> {
     /// assert_eq!(unbounded_string.map(|s| s.len()), Unbounded);
     /// ```
     #[inline]
-    #[stable(feature = "bound_map", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "bound_map", since = "1.77.0")]
     pub fn map<U, F: FnOnce(T) -> U>(self, f: F) -> Bound<U> {
         match self {
             Unbounded => Unbounded,
diff --git a/library/core/src/slice/iter.rs b/library/core/src/slice/iter.rs
@@ -3252,21 +3252,21 @@ unsafe impl<'a, T> TrustedRandomAccessNoCoerce for IterMut<'a, T> {
 ///
 /// [`chunk_by`]: slice::chunk_by
 /// [slices]: slice
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 #[must_use = "iterators are lazy and do nothing unless consumed"]
 pub struct ChunkBy<'a, T: 'a, P> {
     slice: &'a [T],
     predicate: P,
 }
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a, P> ChunkBy<'a, T, P> {
     pub(super) fn new(slice: &'a [T], predicate: P) -> Self {
         ChunkBy { slice, predicate }
     }
 }
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a, P> Iterator for ChunkBy<'a, T, P>
 where
     P: FnMut(&T, &T) -> bool,
@@ -3300,7 +3300,7 @@ where
     }
 }
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a, P> DoubleEndedIterator for ChunkBy<'a, T, P>
 where
     P: FnMut(&T, &T) -> bool,
@@ -3322,10 +3322,10 @@ where
     }
 }
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a, P> FusedIterator for ChunkBy<'a, T, P> where P: FnMut(&T, &T) -> bool {}
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a + fmt::Debug, P> fmt::Debug for ChunkBy<'a, T, P> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_struct("ChunkBy").field("slice", &self.slice).finish()
@@ -3339,21 +3339,21 @@ impl<'a, T: 'a + fmt::Debug, P> fmt::Debug for ChunkBy<'a, T, P> {
 ///
 /// [`chunk_by_mut`]: slice::chunk_by_mut
 /// [slices]: slice
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 #[must_use = "iterators are lazy and do nothing unless consumed"]
 pub struct ChunkByMut<'a, T: 'a, P> {
     slice: &'a mut [T],
     predicate: P,
 }
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a, P> ChunkByMut<'a, T, P> {
     pub(super) fn new(slice: &'a mut [T], predicate: P) -> Self {
         ChunkByMut { slice, predicate }
     }
 }
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a, P> Iterator for ChunkByMut<'a, T, P>
 where
     P: FnMut(&T, &T) -> bool,
@@ -3388,7 +3388,7 @@ where
     }
 }
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a, P> DoubleEndedIterator for ChunkByMut<'a, T, P>
 where
     P: FnMut(&T, &T) -> bool,
@@ -3411,10 +3411,10 @@ where
     }
 }
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a, P> FusedIterator for ChunkByMut<'a, T, P> where P: FnMut(&T, &T) -> bool {}
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 impl<'a, T: 'a + fmt::Debug, P> fmt::Debug for ChunkByMut<'a, T, P> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_struct("ChunkByMut").field("slice", &self.slice).finish()
diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs
@@ -68,7 +68,7 @@ pub use iter::{ArrayChunks, ArrayChunksMut};
 #[unstable(feature = "array_windows", issue = "75027")]
 pub use iter::ArrayWindows;
 
-#[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+#[stable(feature = "slice_group_by", since = "1.77.0")]
 pub use iter::{ChunkBy, ChunkByMut};
 
 #[stable(feature = "split_inclusive", since = "1.51.0")]
@@ -334,8 +334,8 @@ impl<T> [T] {
     /// assert_eq!(Some(&[]), w.first_chunk::<0>());
     /// ```
     #[inline]
-    #[stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
-    #[rustc_const_stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_first_last_chunk", since = "1.77.0")]
+    #[rustc_const_stable(feature = "slice_first_last_chunk", since = "1.77.0")]
     pub const fn first_chunk<const N: usize>(&self) -> Option<&[T; N]> {
         if self.len() < N {
             None
@@ -364,7 +364,7 @@ impl<T> [T] {
     /// assert_eq!(None, x.first_chunk_mut::<4>());
     /// ```
     #[inline]
-    #[stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_first_last_chunk", since = "1.77.0")]
     #[rustc_const_unstable(feature = "const_slice_first_last_chunk", issue = "111774")]
     pub const fn first_chunk_mut<const N: usize>(&mut self) -> Option<&mut [T; N]> {
         if self.len() < N {
@@ -394,8 +394,8 @@ impl<T> [T] {
     /// assert_eq!(None, x.split_first_chunk::<4>());
     /// ```
     #[inline]
-    #[stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
-    #[rustc_const_stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_first_last_chunk", since = "1.77.0")]
+    #[rustc_const_stable(feature = "slice_first_last_chunk", since = "1.77.0")]
     pub const fn split_first_chunk<const N: usize>(&self) -> Option<(&[T; N], &[T])> {
         if self.len() < N {
             None
@@ -429,7 +429,7 @@ impl<T> [T] {
     /// assert_eq!(None, x.split_first_chunk_mut::<4>());
     /// ```
     #[inline]
-    #[stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_first_last_chunk", since = "1.77.0")]
     #[rustc_const_unstable(feature = "const_slice_first_last_chunk", issue = "111774")]
     pub const fn split_first_chunk_mut<const N: usize>(
         &mut self,
@@ -464,8 +464,8 @@ impl<T> [T] {
     /// assert_eq!(None, x.split_last_chunk::<4>());
     /// ```
     #[inline]
-    #[stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
-    #[rustc_const_stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_first_last_chunk", since = "1.77.0")]
+    #[rustc_const_stable(feature = "slice_first_last_chunk", since = "1.77.0")]
     pub const fn split_last_chunk<const N: usize>(&self) -> Option<(&[T], &[T; N])> {
         if self.len() < N {
             None
@@ -499,7 +499,7 @@ impl<T> [T] {
     /// assert_eq!(None, x.split_last_chunk_mut::<4>());
     /// ```
     #[inline]
-    #[stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_first_last_chunk", since = "1.77.0")]
     #[rustc_const_unstable(feature = "const_slice_first_last_chunk", issue = "111774")]
     pub const fn split_last_chunk_mut<const N: usize>(
         &mut self,
@@ -534,7 +534,7 @@ impl<T> [T] {
     /// assert_eq!(Some(&[]), w.last_chunk::<0>());
     /// ```
     #[inline]
-    #[stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_first_last_chunk", since = "1.77.0")]
     #[rustc_const_unstable(feature = "const_slice_first_last_chunk", issue = "111774")]
     pub const fn last_chunk<const N: usize>(&self) -> Option<&[T; N]> {
         if self.len() < N {
@@ -568,7 +568,7 @@ impl<T> [T] {
     /// assert_eq!(None, x.last_chunk_mut::<4>());
     /// ```
     #[inline]
-    #[stable(feature = "slice_first_last_chunk", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_first_last_chunk", since = "1.77.0")]
     #[rustc_const_unstable(feature = "const_slice_first_last_chunk", issue = "111774")]
     pub const fn last_chunk_mut<const N: usize>(&mut self) -> Option<&mut [T; N]> {
         if self.len() < N {
@@ -1777,7 +1777,7 @@ impl<T> [T] {
     /// assert_eq!(iter.next(), Some(&[2, 3, 4][..]));
     /// assert_eq!(iter.next(), None);
     /// ```
-    #[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_group_by", since = "1.77.0")]
     #[inline]
     pub fn chunk_by<F>(&self, pred: F) -> ChunkBy<'_, T, F>
     where
@@ -1818,7 +1818,7 @@ impl<T> [T] {
     /// assert_eq!(iter.next(), Some(&mut [2, 3, 4][..]));
     /// assert_eq!(iter.next(), None);
     /// ```
-    #[stable(feature = "slice_group_by", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "slice_group_by", since = "1.77.0")]
     #[inline]
     pub fn chunk_by_mut<F>(&mut self, pred: F) -> ChunkByMut<'_, T, F>
     where
@@ -1953,7 +1953,7 @@ impl<T> [T] {
     #[unstable(feature = "slice_split_at_unchecked", reason = "new API", issue = "76014")]
     #[rustc_const_stable(
         feature = "const_slice_split_at_unchecked",
-        since = "CURRENT_RUSTC_VERSION"
+        since = "1.77.0"
     )]
     #[inline]
     #[must_use]
diff --git a/library/std/src/f32.rs b/library/std/src/f32.rs
@@ -114,7 +114,7 @@ impl f32 {
     /// ```
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    #[stable(feature = "round_ties_even", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "round_ties_even", since = "1.77.0")]
     #[inline]
     pub fn round_ties_even(self) -> f32 {
         unsafe { intrinsics::rintf32(self) }
diff --git a/library/std/src/f64.rs b/library/std/src/f64.rs
@@ -114,7 +114,7 @@ impl f64 {
     /// ```
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
-    #[stable(feature = "round_ties_even", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "round_ties_even", since = "1.77.0")]
     #[inline]
     pub fn round_ties_even(self) -> f64 {
         unsafe { intrinsics::rintf64(self) }
diff --git a/library/std/src/fs.rs b/library/std/src/fs.rs
@@ -428,7 +428,7 @@ impl File {
     ///     Ok(())
     /// }
     /// ```
-    #[stable(feature = "file_create_new", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "file_create_new", since = "1.77.0")]
     pub fn create_new<P: AsRef<Path>>(path: P) -> io::Result<File> {
         OpenOptions::new().read(true).write(true).create_new(true).open(path.as_ref())
     }
diff --git a/library/std/src/sync/mutex.rs b/library/std/src/sync/mutex.rs
@@ -404,7 +404,7 @@ impl<T: ?Sized> Mutex<T> {
     /// assert_eq!(*x, 1);
     /// ```
     #[inline]
-    #[stable(feature = "mutex_unpoison", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "mutex_unpoison", since = "1.77.0")]
     pub fn clear_poison(&self) {
         self.poison.clear();
     }
diff --git a/library/std/src/sync/rwlock.rs b/library/std/src/sync/rwlock.rs
@@ -408,7 +408,7 @@ impl<T: ?Sized> RwLock<T> {
     /// assert_eq!(*guard, 1);
     /// ```
     #[inline]
-    #[stable(feature = "mutex_unpoison", since = "CURRENT_RUSTC_VERSION")]
+    #[stable(feature = "mutex_unpoison", since = "1.77.0")]
     pub fn clear_poison(&self) {
         self.poison.clear();
     }
diff --git a/src/ci/channel b/src/ci/channel
@@ -1 +1 @@
-nightly
+beta

Original file line number	Diff line number	Diff line change
`@@ -15,7 +15,7 @@ impl<'a, T: Clone> From<&'a [T]> for Cow<'a, [T]> {`
`15`	`15`	`}`
`16`	`16`	`}`
`17`	`17`
`18`		`-#[stable(feature = "cow_from_array_ref", since = "CURRENT_RUSTC_VERSION")]`
	`18`	`+#[stable(feature = "cow_from_array_ref", since = "1.77.0")]`
`19`	`19`	`impl<'a, T: Clone, const N: usize> From<&'a [T; N]> for Cow<'a, [T]> {`
`20`	`20`	/// Creates a [`Borrowed`] variant of [`Cow`]
`21`	`21`	`/// from a reference to an array.`