could not find `__private` in `actix`

[Danny5487401]

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Current Behavior

error[E0433]: failed to resolve: could not find __private in actix --> 33_concurrency/examples/actor.rs:40:1 | 40 | #[actix::main] | ^^^^^^^^^^^^^^ could not find __private in actix

Steps to Reproduce (for bugs)

use actix::prelude::*;
use anyhow::Result;

// actor 可以处理的消息
#[derive(Message, Debug, Clone, PartialEq)]
#[rtype(result = "OutMsg")]
enum InMsg {
    Add((usize, usize)),
    Concat((String, String)),
}

#[derive(MessageResponse, Debug, Clone, PartialEq)]
enum OutMsg {
    Num(usize),
    Str(String),
}

// Actor
struct DummyActor;

impl Actor for DummyActor {
    type Context = Context<Self>;
}

// 实现处理 InMsg 的 Handler trait
impl Handler<InMsg> for DummyActor {
    type Result = OutMsg; // <-  返回的消息

    fn handle(&mut self, msg: InMsg, _ctx: &mut Self::Context) -> Self::Result {
        match msg {
            InMsg::Add((a, b)) => OutMsg::Num(a + b),
            InMsg::Concat((mut s1, s2)) => {
                s1.push_str(&s2);
                OutMsg::Str(s1)
            }
        }
    }
}

#[actix::main]
async fn main() -> Result<()> {
    let addr = DummyActor.start();
    let res = addr.send(InMsg::Add((21, 21))).await?;
    let res1 = addr
        .send(InMsg::Concat(("hello, ".into(), "world".into())))
        .await?;

    println!("res: {:?}, res1: {:?}", res, res1);

    Ok(())
}

Your Environment

• Rust Version (I.e, output of rustc -V):rustc 1.78.0 (9b00956e5 2024-04-29)
• Actix Version: 0.12.0
• actix _derive: 0.6.1