Function crossbeam_channel::tick
source · [−]Expand description
Creates a receiver that delivers messages periodically.
The channel is bounded with capacity of 1 and never gets disconnected. Messages will be
sent into the channel in intervals of duration
. Each message is the instant at which it is
sent.
Examples
Using a tick
channel to periodically print elapsed time:
use std::time::{Duration, Instant};
use crossbeam_channel::tick;
let start = Instant::now();
let ticker = tick(Duration::from_millis(100));
for _ in 0..5 {
ticker.recv().unwrap();
println!("elapsed: {:?}", start.elapsed());
}
When messages get sent:
use std::thread;
use std::time::{Duration, Instant};
use crossbeam_channel::tick;
// Converts a number of milliseconds into a `Duration`.
let ms = |ms| Duration::from_millis(ms);
// Returns `true` if `a` and `b` are very close `Instant`s.
let eq = |a, b| a + ms(50) > b && b + ms(50) > a;
let start = Instant::now();
let r = tick(ms(100));
// This message was sent 100 ms from the start and received 100 ms from the start.
assert!(eq(r.recv().unwrap(), start + ms(100)));
assert!(eq(Instant::now(), start + ms(100)));
thread::sleep(ms(500));
// This message was sent 200 ms from the start and received 600 ms from the start.
assert!(eq(r.recv().unwrap(), start + ms(200)));
assert!(eq(Instant::now(), start + ms(600)));
// This message was sent 700 ms from the start and received 700 ms from the start.
assert!(eq(r.recv().unwrap(), start + ms(700)));
assert!(eq(Instant::now(), start + ms(700)));