1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38

// Copyright (c) 2013-2016 Sandstorm Development Group, Inc. and contributors
// Licensed under the MIT License:
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

use futures::{Future, FutureExt};

use std::cell::RefCell;
use std::rc::{Rc};

pub fn split<F, T1, T2, E>(f: F) -> (impl Future<Output=Result<T1, E>>,
                                     impl Future<Output=Result<T2, E>>)
    where F: Future<Output=Result<(T1, T2), E>>,
          E: Clone,
{
    let shared = f.map(|r| {
        let (v1, v2) = r?;
        Ok(Rc::new(RefCell::new((Some(v1), Some(v2)))))
        }).shared();
    (shared.clone().map(|r| Ok::<T1, E>(r?.borrow_mut().0.take().unwrap())),
     shared.map(|r| Ok::<T2, E>(r?.borrow_mut().1.take().unwrap())))
}