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

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

    let f = future::result(Ok(()))
        .map_err(|()| "&'static str error")
        .and_then(|_|
             future::result(Ok(())
                .map_err(|()| "String error".to_owned())
            )
        )
    ;

    core.run(f).unwrap();
}