ex-futures 0.4.9

An extension of `futures`
Documentation
futures_ext
===

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An extension of `futures`.

[Document](https://docs.rs/ex-futures)


For now, this crate enables you to
- create publish subscribe channel (will be removed future)
- convert any kind of stream/sink into "cloneable"
- fork any kind of stream
- convert `Error` associated type which is `()`


## How to use
### Publish-Subscribe channel
An usage is almost same with `futures::unsync::mpsc::unbounded`.


```rust
use ex_futures::unsync::pubsub::unbounded;

fn main() {
    let (tx, rx) = unbounded::<usize>();
    let rx2 = rx.clone();
    let mut rx = rx.wait();
    let mut rx2 = rx.wait(); // Subscriber is cloneable

    tx.send(1).wait().unwrap();

    assert_eq!(rx.next().unwrap().map(|i| *i), Ok(1));
    assert_eq!(rx2.next().unwrap().map(|i| *i), Ok(1));
}
```


### Cloneable stream/sink

```rust
use ex_futures::StreamExt;
use futures::unsycn::mpsc::channel;

fn main() {
    let (tx, rx) = channel(42);;

    let cloneable_rx = rx.unsync_cloneable(); // Convert "rx" into cloneable
    let cloneable_rx2 = cloneable.clone();  // Now you can clone it

    let tx = tx.wait();
    tx.send(0);
    tx.send(1);
    tx.send(2);
    tx.send(3);

    assert_eq!(cloneable_rx.collect().wait().unwrap(), [0, 1, 2, 3]);
    assert_eq!(cloneable_rx2.collect().wait().unwrap(), [0, 1, 2, 3]);
}
```


### Forked stream

```rust
use ex_futures::StreamExt;

fn main() {
    let int_stream = gen_stream(); // Somehow you create some stream

    let (even, odd) = int_stream.fork(|i| i % 2 == 0);

    assert_eq!(even.collect().wait().unwrap(), [0, 2]);
    assert_eq!(odd.collect().wait().unwrap(), [1, 3]);
}
```