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|
// run-pass
#![allow(unused_must_use)]
fn main() {
if false { test(); }
}
fn test() {
let rx = Err::<Vec<usize>, u32>(1).into_future();
rx.map(|l: Vec<usize>| stream::iter(l.into_iter().map(|i| Ok(i))))
.flatten_stream()
.chunks(50)
.buffer_unordered(5);
}
use future::{Future, IntoFuture};
mod future {
use std::result;
use {stream, Stream};
pub trait Future {
type Item;
type Error;
fn map<F, U>(self, _: F) -> Map<Self, F>
where F: FnOnce(Self::Item) -> U,
Self: Sized,
{
panic!()
}
fn flatten_stream(self) -> FlattenStream<Self>
where <Self as Future>::Item: stream::Stream<Error=Self::Error>,
Self: Sized
{
panic!()
}
}
pub 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 {
panic!()
}
}
impl<T, E> IntoFuture for result::Result<T, E> {
type Future = FutureResult<T, E>;
type Item = T;
type Error = E;
fn into_future(self) -> FutureResult<T, E> {
panic!()
}
}
pub struct Map<A, F> {
_a: (A, F),
}
impl<U, A, F> Future for Map<A, F>
where A: Future,
F: FnOnce(A::Item) -> U,
{
type Item = U;
type Error = A::Error;
}
pub struct FlattenStream<F> {
_f: F,
}
impl<F> Stream for FlattenStream<F>
where F: Future,
<F as Future>::Item: Stream<Error=F::Error>,
{
type Item = <F::Item as Stream>::Item;
type Error = <F::Item as Stream>::Error;
}
pub struct FutureResult<T, E> {
_inner: (T, E),
}
impl<T, E> Future for FutureResult<T, E> {
type Item = T;
type Error = E;
}
}
mod stream {
use IntoFuture;
pub trait Stream {
type Item;
type Error;
fn buffer_unordered(self, amt: usize) -> BufferUnordered<Self>
where Self::Item: IntoFuture<Error = <Self as Stream>::Error>,
Self: Sized
{
new(self, amt)
}
fn chunks(self, _capacity: usize) -> Chunks<Self>
where Self: Sized
{
panic!()
}
}
pub struct IterStream<I> {
_iter: I,
}
pub fn iter<J, T, E>(_: J) -> IterStream<J::IntoIter>
where J: IntoIterator<Item=Result<T, E>>,
{
panic!()
}
impl<I, T, E> Stream for IterStream<I>
where I: Iterator<Item=Result<T, E>>,
{
type Item = T;
type Error = E;
}
pub struct Chunks<S> {
_stream: S
}
impl<S> Stream for Chunks<S>
where S: Stream
{
type Item = Result<Vec<<S as Stream>::Item>, u32>;
type Error = <S as Stream>::Error;
}
pub struct BufferUnordered<S> {
_stream: S,
}
enum Slot<T> {
Next(#[allow(unused_tuple_struct_fields)] usize),
_Data { _a: T },
}
fn new<S>(_s: S, _amt: usize) -> BufferUnordered<S>
where S: Stream,
S::Item: IntoFuture<Error=<S as Stream>::Error>,
{
(0..0).map(|_| {
Slot::Next::<<S::Item as IntoFuture>::Future>(1)
}).collect::<Vec<_>>();
panic!()
}
impl<S> Stream for BufferUnordered<S>
where S: Stream,
S::Item: IntoFuture<Error=<S as Stream>::Error>,
{
type Item = <S::Item as IntoFuture>::Item;
type Error = <S as Stream>::Error;
}
}
use stream::Stream;
|
