Reverse PR `#26944 `, symbol `#` are actually as intended.
/// The following two examples are equivalent:
///
/// ```
/// The following two examples are equivalent:
///
/// ```
-/// #![feature(box_heap)]
+/// # #![feature(box_heap)]
/// #![feature(box_syntax)]
/// use std::boxed::HEAP;
///
/// #![feature(box_syntax)]
/// use std::boxed::HEAP;
///
///
/// # Examples
/// ```
///
/// # Examples
/// ```
-/// #![feature(box_raw)]
+/// # #![feature(box_raw)]
/// use std::boxed;
///
/// let seventeen = Box::new(17u32);
/// use std::boxed;
///
/// let seventeen = Box::new(17u32);