From 6c8993532c7799c745247fb7dc6293156e5c5b05 Mon Sep 17 00:00:00 2001
From: Ethan Dagner <napen123@gmail.com>
Date: Sat, 9 Sep 2017 10:27:47 -0600
Subject: [PATCH] Add doc examples for str::as_bytes_mut

Fixes #44427
---
 src/liballoc/str.rs | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/src/liballoc/str.rs b/src/liballoc/str.rs
index 79b2bbce2af7c..c1252b219c47d 100644
--- a/src/liballoc/str.rs
+++ b/src/liballoc/str.rs
@@ -297,6 +297,34 @@ impl str {
     /// [`str::from_utf8_mut`] function.
     ///
     /// [`str::from_utf8_mut`]: ./str/fn.from_utf8_mut.html
+    ///
+    /// # Examples
+    ///
+    /// Basic usage:
+    ///
+    /// ```
+    /// let mut s = String::from("Hello");
+    /// let bytes = unsafe { s.as_bytes_mut() };
+    ///
+    /// assert_eq!(b"Hello", bytes);
+    /// ```
+    ///
+    /// Mutability:
+    ///
+    /// ```
+    /// let mut s = String::from("🗻∈🌏");
+    ///
+    /// unsafe {
+    ///     let bytes = s.as_bytes_mut();
+    ///
+    ///     bytes[0] = 0xF0;
+    ///     bytes[1] = 0x9F;
+    ///     bytes[2] = 0x8D;
+    ///     bytes[3] = 0x94;
+    /// }
+    ///
+    /// assert_eq!("🍔∈🌏", s);
+    /// ```
     #[stable(feature = "str_mut_extras", since = "1.20.0")]
     #[inline(always)]
     pub unsafe fn as_bytes_mut(&mut self) -> &mut [u8] {