--- /dev/null
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use std::marker;
+use std::mem;
+
+fn main() {
+ let workers = (0..0).map(|_| result::<u32, ()>());
+ drop(join_all(workers).poll());
+}
+
+trait Future {
+ type Item;
+ type Error;
+
+ fn poll(&mut self) -> Result<Self::Item, Self::Error>;
+}
+
+trait IntoFuture {
+ type Future: Future<Item=Self::Item, Error=Self::Error>;
+ type Item;
+ type Error;
+
+ fn into_future(self) -> Self::Future;
+}
+
+impl<F: Future> IntoFuture for F {
+ type Future = F;
+ type Item = F::Item;
+ type Error = F::Error;
+
+ fn into_future(self) -> F {
+ self
+ }
+}
+
+struct FutureResult<T, E> {
+ _inner: marker::PhantomData<(T, E)>,
+}
+
+fn result<T, E>() -> FutureResult<T, E> {
+ loop {}
+}
+
+impl<T, E> Future for FutureResult<T, E> {
+ type Item = T;
+ type Error = E;
+
+ fn poll(&mut self) -> Result<T, E> {
+ loop {}
+ }
+}
+
+struct JoinAll<I>
+ where I: IntoIterator,
+ I::Item: IntoFuture,
+{
+ elems: Vec<<I::Item as IntoFuture>::Item>,
+}
+
+fn join_all<I>(_: I) -> JoinAll<I>
+ where I: IntoIterator,
+ I::Item: IntoFuture,
+{
+ JoinAll { elems: vec![] }
+}
+
+impl<I> Future for JoinAll<I>
+ where I: IntoIterator,
+ I::Item: IntoFuture,
+{
+ type Item = Vec<<I::Item as IntoFuture>::Item>;
+ type Error = <I::Item as IntoFuture>::Error;
+
+ fn poll(&mut self) -> Result<Self::Item, Self::Error> {
+ let elems = mem::replace(&mut self.elems, Vec::new());
+ Ok(elems.into_iter().map(|e| {
+ e
+ }).collect::<Vec<_>>())
+ }
+}