trpl-zh-cn/listings/ch17-async-await/listing-17-26/src/main.rs

extern crate trpl; // required for mdbook test

use std::time::{Duration, Instant};

fn main() {
    trpl::run(async {
        // ANCHOR: here
        let one_ns = Duration::from_nanos(1);
        let start = Instant::now();
        async {
            for _ in 1..1000 {
                trpl::sleep(one_ns).await;
            }
        }
        .await;
        let time = Instant::now() - start;
        println!(
            "'sleep' version finished after {} seconds.",
            time.as_secs_f32()
        );

        let start = Instant::now();
        async {
            for _ in 1..1000 {
                trpl::yield_now().await;
            }
        }
        .await;
        let time = Instant::now() - start;
        println!(
            "'yield' version finished after {} seconds.",
            time.as_secs_f32()
        );
        // ANCHOR_END: here
    });
}