Format panic docs for split_at

Fixes #28384

diff --git a/src/libcollections/slice.rs b/src/libcollections/slice.rs
index 76bdd6dbea1221a69da5864a649ebb97f8233b20..dabfd168c89ac3557dffed06fe20a3352efe048b 100644 (file)
--- a/src/libcollections/slice.rs
+++ b/src/libcollections/slice.rs
@@ -455,6 +455,8 @@ pub fn chunks_mut(&mut self, chunk_size: usize) -> ChunksMut<T> {
     /// the index `mid` itself) and the second will contain all
     /// indices from `[mid, len)` (excluding the index `len` itself).
     ///
+    /// # Panics
+    ///
     /// Panics if `mid > len`.
     ///
     /// # Examples