1. 为什么Rust的main函数不能是async的? Rust的main函数是程序的入口点,它必须是一个同步函数。这是因为异步函数需要依赖运行时(Runtime)来调度和执行异步任务,而main函数本身并不具备这样的能力。如果允许main函数是异步的,那么程序在启动时就没有一个明确的同步点来初始化运行时和调度异步任务,这会导致程序无法正...
`main` function is not allowed to be `async` [dependencies] tokio = { version = "0.3", features = ["macros", "sync"] } #[tokio::main] main 又报错The #[tokio::main] macro requires rt or rt-multi-thread. 换成 tokio = { version = "1.24.2", features = ["full"] } tokio-tes...
error[E0433]:failed to resolve:useofundeclared crate or module`actix_rt`-->backend\src\main.rs:7:3|7|#[actix_rt::main]|^^^useofundeclared crate or module`actix_rt`…… …… error[E0752]:`main`functionis not allowed to be`async`-->backend\src\main.rs:8:1|8|asyncfnmain()->st...
thread'tests::test_sync_method'panickedat'Cannotstartaruntimefromwithinaruntime.Thishappensbecauseafunction(like`block_on`)attemptedtoblockthecurrentthreadwhilethethreadisbeingusedtodriveasynchronoustasks.',/Users/lei/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.17.0/src/runtime/enter.rs9...
32 | | self.generate_async().await | | ^^^ only allowed inside `async` functions and blocks 33 | | } | |___- this is not `async` 我们首先想到的是,Tokio 的 runtime 有一个Runtime::block_on方法,可以同步地等待一个 future 完成。 implSequencer...
Xactor is a rust actors framework based on async-std。 1. 速度比actix快40%(见后面测试,为部分性能),具体原因还不清楚,需要研究一下actix内部实现,晚点发和几个现有框架对比的性能测试代码 2. 完全兼容await语法,不是actix那样自己一套future体系,容易和其它支持await的库结合使用 增加与actix的性能对比 https...
Full example async fn go<'a>(value: &'a i32) { let closure = async |scope: ScopeRef<'_, 'a>| { let _future1 = scope.spawn(async { let _v = *value; }); }; } yields error: lifetime may not live long enough --> examples/repro.rs:52:63 | 52 ...
With the synchronous call, themainfunction needs to wait until the file is loaded from the file system. Only then can it call thefoofunction, which requires it to again wait for the result. With the asynchronousasync_read_filecall, the file system directly returns a future and loads the fi...
usestd::future::Future;usestd::pin::Pin;asyncfnrecurse(i:usize){ifi ==0{println!("Zero!");return;}println!("entering {}", i);(Box::pin(recurse(i-1))asPin<Box<dynFuture<Output=()>>>).await;println!("exiting {}", i);}fnmain(){futures::executor::block_on(recurse(10));}...
可以工作？错误消息有点误导，因为它表示在类型约束解析期间出现的中间问题。同样的问题可以在没有async的...