With #125 out, it's probably worth looking at which other parts of std::iter we can port to async_std::stream. This issue is intended to track what's left for us to port.

Missing free functions

• from_fn
• repeat_with
• successors

Missing traits

• DoubleEndedStream
• ExactSizeStream
• Extend
• FusedStream
• Product
• Sum

Missing stream methods

• Stream::all
• Stream::any
• Stream::by_ref
• Stream::chain
• Stream::cloned
• Stream::cmp
• Stream::collect
• Stream::copied
• Stream::count
• Stream::cycle
• Stream::enumerate
• Stream::eq
• Stream::filter
• Stream::filter_map
• Stream::find
• Stream::find_map
• Stream::flat_map
• Stream::flatten
• Stream::fold
• Stream::for_each
• Stream::fuse
• Stream::ge
• Stream::gt
• Stream::inspect
• Stream::last
• Stream::le
• Stream::lt
• Stream::map
• Stream::max
• Stream::max_by
• Stream::max_by_key
• Stream::min
• Stream::min_by
• Stream::min_by_key
• Stream::ne
• Stream::nth
• Stream::partial_cmp
• Stream::partition
• Stream::peekable -> wip add stream::peekable #366
• Stream::position
• Stream::product
• Stream::rev
• Stream::rposition
• Stream::scan
• Stream::size_hint
• Stream::skip
• Stream::skip_while
• Stream::step_by
• Stream::sum
• Stream::take
• Stream::take_while
• Stream::try_fold
• Stream::try_for_each
• Stream::unzip
• Stream::zip

(削除) Missing IntoStream impls (削除ここまで)

Currently not possible. See #129 (comment)

Missing FromStream impls

• FromStream<()> for ()
• FromStream<char> for String
• FromStream<String> for String
• FromStream<&'a char> for String
• FromStream<&'a str> for String
• FromStream<T> for Cow<'a, [T]> where T: Clone
• FromStream<A> for Box<[A]>
• FromStream<A> for VecDeque<A>
• FromStream<Result<A, E>> for Result<V, E> where V: FromStream<A>
• FromStream<Option<A>> for Option<V> where V: FromStream<A>
• FromStream<(K, V)> for BTreeMap<K, V> where K: Ord
• FromStream<(K, V)> for HashMap<K, V, S> where K: Eq + Hash, S: BuildHasher + Default
• FromStream<T> for BinaryHeap<T> where T: Ord
• FromStream<T> for BTreeSet<T> where T: Ord
• FromStream<T> for LinkedList<T>
• FromStream<T> for Vec<T>
• FromStream<T> for HashSet<T, S> where T: Eq + Hash, S: BuildHasher + Default

DoubleEndedStream

• DoubleEndedStream::poll_next_back
• DoubleEndedStream::next_back
• DoubleEndedStream::nth_back
• DoubleEndedStream::rfind
• DoubleEndedStream::rfold
• DoubleEndedStream::try_rfold