Update docs

src/iter/mod.rs

@@ -1962,6 +1962,9 @@ pub trait ParallelIterator: Sized + Send {
     /// of how many elements the iterator contains, and even allows you to reuse
     /// an existing vector's backing store rather than allocating a fresh vector.
     ///
+    /// See also [`collect_vec_list()`][Self::collect_vec_list] for collecting
+    /// into a `LinkedList<Vec<T>>`.
+    ///
     /// [`IndexedParallelIterator`]: trait.IndexedParallelIterator.html
     /// [`collect_into_vec()`]:
     ///     trait.IndexedParallelIterator.html#method.collect_into_vec
@@ -2367,7 +2370,9 @@ pub trait ParallelIterator: Sized + Send {
     ///     .flat_map(|x| 0..x)
     ///     .collect_vec_list();
     ///
-    /// let total_len = result.iter().flatten().count();
+    /// // `par_iter.collect_vec_list().into_iter().flatten()` turns
+    /// // a parallel iterator into a serial one
+    /// let total_len = result.into_iter().flatten().count();
     /// assert_eq!(total_len, 2550);
     /// ```
     fn collect_vec_list(self) -> LinkedList<Vec<Self::Item>> {
@@ -3232,14 +3237,15 @@ where
     ///
     /// If your collection is not naturally parallel, the easiest (and
     /// fastest) way to do this is often to collect `par_iter` into a
-    /// [`LinkedList`] or other intermediate data structure and then
-    /// sequentially extend your collection. However, a more 'native'
-    /// technique is to use the [`par_iter.fold`] or
+    /// [`LinkedList`] (via [`collect_vec_list`]) or another intermediate
+    /// data structure and then sequentially extend your collection. However,
+    /// a more 'native' technique is to use the [`par_iter.fold`] or
     /// [`par_iter.fold_with`] methods to create the collection.
     /// Alternatively, if your collection is 'natively' parallel, you
     /// can use `par_iter.for_each` to process each element in turn.
     ///
     /// [`LinkedList`]: https://doc.rust-lang.org/std/collections/struct.LinkedList.html
+    /// [`collect_vec_list`]: ParallelIterator::collect_vec_list
     /// [`par_iter.fold`]: trait.ParallelIterator.html#method.fold
     /// [`par_iter.fold_with`]: trait.ParallelIterator.html#method.fold_with
     /// [`par_iter.for_each`]: trait.ParallelIterator.html#method.for_each