async fn main() { let start = std::time::Instant::now(); stream::iter(1..=50000) .map(|i| async move { print_with_delay(i).await }) .buffer_unordered(CONCURRENT_LIMIT) .collect::<Vec<()>>() .await; let duration = start.elapsed(); println!("Total time: {:?}", duration)...
("Error level - description");errors.iter().enumerate().for_each(|(index,error)|eprintln!("└> {} - {}",index,error));ifletSome(backtrace)=errors.backtrace(){eprintln!("{:?}",backtrace);}// In a real use case, errors should handled. For example:// ::std::process::exit(1)...
structYieldNow{is_ready:bool}implFutureforYieldNow{typeOutput=();fnpoll(self:Pin<&mutSelf>,cx:&mutContext<'_>)->Poll<()>{ifself.is_ready{returnPoll::Ready(());}self.is_ready=true;// 通知调用方,自己有“进展”cx.waker().wake_by_ref();// 交还控制流Poll::Pending}}pubasyncfnyield...
这个习惯用法的一个常见用法是处理孤立规则，并为别名类型定义特征实现。例如，下面的代码定义了一种以十六进制显示字节向量的新类型。struct Hex(Vec<u8>);impl std::fmt::Display for Hex {fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {self.0.iter().try_for_each(|b...
fn echo_requests_iter() -> impl Stream { tokio_stream::iter(1..usize::MAX).map(|i| EchoRequest { message: format!("msg {:02}", i), })} async fn unary_echo(client: &mut EchoClient, num: usize) { for i in 0..num { let req = tonic::Request::new(EchoRequest { message:...
Rust allows a program to iterate over any typeTin aforloop, as long asTimplements theIteratortrait. traitIterator{typeItem;fnnext(&mutself)->Option<Self::Item>; }traitIntoIteratorwhereSelf::IntoIter::Item ==Self::Item {typeItem;typeIntoIter:Iterator;fninto_iter(self)->Self::IntoIter; ...
;// Download and save images to ./data directory.// Each url is downloaded and saved in dedicated Tokio task.// Directory is created if it doesn't exist.letpaths = response.save("./data").await?;paths.iter().for_each(|path|println!("Image file path: {}",path.display()));Ok((...
thread::spawn(move || receiver.iter().for_each(|task| task.run())); } sender }); type Task = async_task::Task<()>; type JoinHandle<R> = Pin<Box<dyn Future<Output = R> + Send>>; fn spawn<F, R>(future: F) -> JoinHandle<R> ...
Further minimized for the remaining error.. playground use futures::stream; use futures::stream::StreamExt; use std::future::{self, Future}; fn get_foo<'a>() -> impl Future<Output = Vec<()>> + 'a { async { let results = vec![()]; let foo: Vec<()> = stream::iter(results...
(0..10).for_each(|i| { tx.send(i).unwrap(); }) }); letreceived:u32= rx.iter().sum(); assert_eq!((0..10).sum::(), received); } 为什么选择 Flume? 功能丰富: Unbounded, bounded 和 rendezvous 队列 快速: 通常比 std::sync::mpsc 更快,某些情况比 crossb...