other kinds of blocking, consider password hashing functions like bcrypt [http://bcrypt.sourceforge.net/], which by design use hundreds of milliseconds of CPU time, far more than a typical network or disk patterns much simpler. do not run at all unless you await or yield them. Decorated coroutines can start running “in the background” as soon as they are called. Note that for both kinds of coroutines it the coroutine runner will not start).Finally, at the top level of a program, if the IOLoop is not yet running, you can start the IOLoop, run the coroutine, and then stop the IOLoop with the IOLoop.run_sync

patterns much simpler. – do not run at all unless you await or yield them. Decorated coroutines can start running “in the back- ground” as soon as they are called. Note that for both kinds of coroutines it the coroutine runner will not start). Finally, at the top level of a program, if the IOLoop is not yet running, you can start the IOLoop, run the coroutine, and then stop the IOLoop with the IOLoop.run_sync run_sync method. This is often used to start the main function of a batch-oriented program: # run_sync() doesn't take arguments, so we must wrap the # call in a lambda. IOLoop.current().run_sync(lambda:

语句引入到作用域的 Rng trait 定义。 gen_range 方法获取一个范围表达式（range expression）作为参数，并生成一个在此范围之 间的随机数。这里使用的这类范围表达式使用了 start..=end 这样的形式，它对上下边界均为 闭区间，所以需要指定 1..=100 来请求一个 1 和 100 之间的数。 29/562Rust 程序设计语言 简体中文版 注意：你不可能凭空就知道应该 值，那么调用 unwrap 也是完全可以接受的，更好的做法是在 expect 的提示文本 中说明你认为永远不会出现 Err 的原因。下面是一个示例：。这里是一个例子： use std::net::IpAddr; let home: IpAddr = "127.0.0.1" .parse() .expect("Hardcoded IP address trpl::yield_now 的 future 的运行时间。 文件名：src/main.rs let one_ns = Duration::from_nanos(1); let start = Instant::now(); async { for _ in 1..1000 { trpl::sleep(one_ns)