futuretest/src/main.rs

#![feature(conservative_impl_trait)]

extern crate futures;
extern crate tokio_core;
use futures::future::{self};
use futures::future::*;
use tokio_core::reactor::Core;

enum ErrorCode
{
    Case1,
    Case2,
}

fn main() {
    let mut core = Core::new().expect("Failed to initialize tokio_core reactor!");

    let f = async_entry_point()
        .or_else(move |err| {
            //the problem is that the three matches below resolve to different anonymized types
            match err {
                ErrorCode::Case1 => case1(),
                ErrorCode::Case2 => case2(),
            }
        })
    ;

    core.run(f);
}

fn async_entry_point() -> impl Future<Item=(), Error=ErrorCode> {
    future::ok(())
}

fn case1() -> impl Future<Item=(), Error=ErrorCode> {
    future::ok(())
}

fn case2() -> impl Future<Item=(), Error=ErrorCode> {
    future::ok(())
}