signal: Ctrl+C example: Defer stream initialisation (and explain how/why)

This commit is contained in:
Jules Kerssemakers 2017-06-08 15:57:06 +02:00 committed by Carl Lerche
parent 1c893ef6d3
commit 6a7092b9f7

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@ -2,7 +2,7 @@ extern crate futures;
extern crate tokio_core;
extern crate tokio_signal;
use futures::stream::Stream;
use futures::{Stream, Future};
use tokio_core::reactor::Core;
fn main() {
@ -10,9 +10,13 @@ fn main() {
let mut core = Core::new().unwrap();
// tokio_signal provides a convenience builder for Ctrl+C
// this even works cross-platform, linux and windows!
let ctrlc = tokio_signal::ctrl_c(&core.handle());
let stream = core.run(ctrlc).unwrap();
// this even works cross-platform: linux and windows!
//
// `fn ctrl_c()` produces a `Future` of the actual stream-initialisation
// the `flatten_stream()` convenience method lazily defers that
// initialisation, allowing us to use it 'as if' it is already the
// stream we want, reducing boilerplate Future-handling.
let stream = tokio_signal::ctrl_c(&core.handle()).flatten_stream();
println!("This program is now waiting for you to press Ctrl+C");