Rename Range::ensure_subset_of to slice::range

library/alloc/src/collections/vec_deque/mod.rs

@@ -1063,7 +1063,7 @@ impl<T> VecDeque<T> {
     where
         R: RangeBounds<usize>,
     {
-        let Range { start, end } = Range::ensure_subset_of(range, ..self.len());
+        let Range { start, end } = slice::range(range, ..self.len());
         let tail = self.wrap_add(self.tail, start);
         let head = self.wrap_add(self.tail, end);
         (tail, head)

library/alloc/src/lib.rs

@@ -115,7 +115,6 @@
 #![feature(or_patterns)]
 #![feature(pattern)]
 #![feature(ptr_internals)]
-#![feature(range_ensure_subset_of)]
 #![feature(rustc_attrs)]
 #![feature(receiver_trait)]
 #![cfg_attr(bootstrap, feature(min_const_generics))]
@@ -123,6 +122,7 @@
 #![feature(set_ptr_value)]
 #![feature(slice_ptr_get)]
 #![feature(slice_ptr_len)]
+#![feature(slice_range)]
 #![feature(staged_api)]
 #![feature(str_internals)]
 #![feature(trusted_len)]

library/alloc/src/slice.rs

@@ -92,6 +92,8 @@ use crate::borrow::ToOwned;
 use crate::boxed::Box;
 use crate::vec::Vec;
 
+#[unstable(feature = "slice_range", issue = "76393")]
+pub use core::slice::range;
 #[unstable(feature = "array_chunks", issue = "74985")]
 pub use core::slice::ArrayChunks;
 #[unstable(feature = "array_chunks", issue = "74985")]

library/alloc/src/string.rs

@@ -49,6 +49,7 @@ use core::iter::{FromIterator, FusedIterator};
 use core::ops::Bound::{Excluded, Included, Unbounded};
 use core::ops::{self, Add, AddAssign, Index, IndexMut, Range, RangeBounds};
 use core::ptr;
+use core::slice;
 use core::str::{lossy, pattern::Pattern};
 
 use crate::borrow::{Cow, ToOwned};
@@ -1510,14 +1511,14 @@ impl String {
         // of the vector version. The data is just plain bytes.
         // Because the range removal happens in Drop, if the Drain iterator is leaked,
         // the removal will not happen.
-        let Range { start, end } = Range::ensure_subset_of(range, ..self.len());
+        let Range { start, end } = slice::range(range, ..self.len());
         assert!(self.is_char_boundary(start));
         assert!(self.is_char_boundary(end));
 
         // Take out two simultaneous borrows. The &mut String won't be accessed
         // until iteration is over, in Drop.
         let self_ptr = self as *mut _;
-        // SAFETY: `ensure_subset_of` and `is_char_boundary` do the appropriate bounds checks.
+        // SAFETY: `slice::range` and `is_char_boundary` do the appropriate bounds checks.
         let chars_iter = unsafe { self.get_unchecked(start..end) }.chars();
 
         Drain { start, end, iter: chars_iter, string: self_ptr }

library/alloc/src/vec/mod.rs

@@ -1650,7 +1650,7 @@ impl<T, A: Allocator> Vec<T, A> {
         // the hole, and the vector length is restored to the new length.
         //
         let len = self.len();
-        let Range { start, end } = Range::ensure_subset_of(range, ..len);
+        let Range { start, end } = slice::range(range, ..len);
 
         unsafe {
             // set self.vec length's to start, to be safe in case Drain is leaked