Put slicing syntax behind a feature gate.

[breaking-change]

If you are using slicing syntax you will need to add #![feature(slicing_syntax)] to your crate.

3 files changed, 7 insertions, 6 deletions

diff --git a/src/libcore/lib.rs b/src/libcore/lib.rs
index 7e2ea492d4c..4890dc2bb73 100644
--- a/src/libcore/lib.rs
+++ b/src/libcore/lib.rs
@@ -57,8 +57,9 @@
        html_playground_url = "http://play.rust-lang.org/")]
 
 #![no_std]
+#![allow(unknown_features)]
 #![feature(globs, intrinsics, lang_items, macro_rules, managed_boxes, phase)]
-#![feature(simd, unsafe_destructor)]
+#![feature(simd, unsafe_destructor, slicing_syntax)]
 #![deny(missing_doc)]
 
 mod macros;
diff --git a/src/libcore/ops.rs b/src/libcore/ops.rs
index 77cee2b9863..422c496995b 100644
--- a/src/libcore/ops.rs
+++ b/src/libcore/ops.rs
@@ -684,7 +684,7 @@ pub trait IndexMut<Index, Result> {
  * A trivial implementation of `Slice`. When `Foo[..Foo]` happens, it ends up
  * calling `slice_to`, and therefore, `main` prints `Slicing!`.
  *
- * ```
+ * ```ignore
  * struct Foo;
  *
  * impl ::core::ops::Slice<Foo, Foo> for Foo {
@@ -749,7 +749,7 @@ pub trait Slice<Idx, Sized? Result> for Sized? {
  * A trivial implementation of `SliceMut`. When `Foo[Foo..]` happens, it ends up
  * calling `slice_from_mut`, and therefore, `main` prints `Slicing!`.
  *
- * ```
+ * ```ignore
  * struct Foo;
  *
  * impl ::core::ops::SliceMut<Foo, Foo> for Foo {
@@ -771,7 +771,7 @@ pub trait Slice<Idx, Sized? Result> for Sized? {
  *     }
  * }
  *
- * fn main() {
+ * pub fn main() {
  *     Foo[mut Foo..];
  * }
  * ```
diff --git a/src/libcore/slice.rs b/src/libcore/slice.rs
index 68b3a3199df..2ff0fd2ef00 100644
--- a/src/libcore/slice.rs
+++ b/src/libcore/slice.rs
@@ -814,13 +814,13 @@ impl<'a,T> MutableSlice<'a, T> for &'a mut [T] {
     #[inline]
     fn tail_mut(self) -> &'a mut [T] {
         let len = self.len();
-        self.slice_mut(1, len)
+        self[mut 1..len]
     }
 
     #[inline]
     fn init_mut(self) -> &'a mut [T] {
         let len = self.len();
-        self.slice_mut(0, len - 1)
+        self[mut 0..len - 1]
     }
 
     #[inline]