Stabilize substr_range and related methods

Author: wr7

library/core/src/slice/mod.rs

@@ -4738,8 +4738,6 @@ impl<T> [T] {
     /// # Examples
     /// Basic usage:
     /// ```
-    /// #![feature(substr_range)]
-    ///
     /// let nums: &[u32] = &[1, 7, 1, 1];
     /// let num = &nums[2];
     ///
@@ -4748,8 +4746,6 @@ impl<T> [T] {
     /// ```
     /// Returning `None` with an unaligned element:
     /// ```
-    /// #![feature(substr_range)]
-    ///
     /// let arr: &[[u32; 2]] = &[[0, 1], [2, 3]];
     /// let flat_arr: &[u32] = arr.as_flattened();
     ///
@@ -4763,7 +4759,7 @@ impl<T> [T] {
     /// assert_eq!(arr.element_offset(weird_elm), None); // Points between element 0 and 1
     /// ```
     #[must_use]
-    #[unstable(feature = "substr_range", issue = "126769")]
+    #[stable(feature = "substr_range", since = "CURRENT_RUSTC_VERSION")]
     pub fn element_offset(&self, element: &T) -> Option<usize> {
         if T::IS_ZST {
             panic!("elements are zero-sized");
@@ -4803,8 +4799,6 @@ impl<T> [T] {
     /// # Examples
     /// Basic usage:
     /// ```
-    /// #![feature(substr_range)]
-    ///
     /// let nums = &[0, 5, 10, 0, 0, 5];
     ///
     /// let mut iter = nums
@@ -4817,7 +4811,7 @@ impl<T> [T] {
     /// assert_eq!(iter.next(), Some(5..6));
     /// ```
     #[must_use]
-    #[unstable(feature = "substr_range", issue = "126769")]
+    #[stable(feature = "substr_range", since = "CURRENT_RUSTC_VERSION")]
     pub fn subslice_range(&self, subslice: &[T]) -> Option<Range<usize>> {
         if T::IS_ZST {
             panic!("elements are zero-sized");

library/core/src/str/mod.rs

@@ -2950,8 +2950,6 @@ impl str {
     ///
     /// # Examples
     /// ```
-    /// #![feature(substr_range)]
-    ///
     /// let data = "a, b, b, a";
     /// let mut iter = data.split(", ").map(|s| data.substr_range(s).unwrap());
     ///
@@ -2961,7 +2959,7 @@ impl str {
     /// assert_eq!(iter.next(), Some(9..10));
     /// ```
     #[must_use]
-    #[unstable(feature = "substr_range", issue = "126769")]
+    #[stable(feature = "substr_range", since = "CURRENT_RUSTC_VERSION")]
     pub fn substr_range(&self, substr: &str) -> Option<Range<usize>> {
         self.as_bytes().subslice_range(substr.as_bytes())
     }