Fix trailing whitespace, punctuation

Author: wmstack

library/core/src/iter/traits/peekable.rs

@@ -17,7 +17,7 @@ pub trait PeekableIterator: Iterator {
     /// assert_eq!(vals.next(), Some(0));
     ///
     /// // examine the pending element
-    /// assert_eq!(vals.peek_with(|x| x), Some(&1));
+    /// assert_eq!(vals.peek_with(|x| x.copied()), Some(1));
     /// assert_eq!(vals.next(), Some(1));
     ///
     /// // determine if the iterator has an element without advancing
@@ -26,7 +26,7 @@ pub trait PeekableIterator: Iterator {
     ///
     /// // exhausted iterator
     /// assert_eq!(vals.next(), None);
-    /// assert_eq!(vals.peek_with(|x| x), None);
+    /// assert_eq!(vals.peek_with(|x| x.copied()), None);
     /// ```
     fn peek_with<T>(&mut self, func: impl for<'a> FnOnce(Option<&'a Self::Item>) -> T) -> T;
 
@@ -50,7 +50,7 @@ pub trait PeekableIterator: Iterator {
     ///     } else {
     ///       10
     ///     }
-    ///     
+    ///
     ///     u32::from_str_radix(c.as_str(), base).unwrap()
     /// }
     ///

library/core/src/slice/iter/macros.rs

@@ -475,9 +475,9 @@ macro_rules! iterator {
                 if len!(self) == 0 {
                     func(None)
                 } else {
-                    // SAFETY: element within bounds as len > 0
-                    // Reference is dropped after the closure completes
-                    // and can not outlive the mutable borrow of self
+                    // SAFETY: Element within bounds as len > 0.
+                    // The reference is dropped after the closure completes
+                    // and can not outlive the mutable borrow of self.
                     let tmp = unsafe { & $( $mut_ )? *self.ptr.as_ptr() };
                     func(Some(tmp).as_ref())
                 }