推断为`FnMut`闭包

Question

我正在尝试迭代向量并将多个异步任务添加到东京计划中，但它抛出错误

inferred to be a FnMut closure

我尝试过克隆数据变量，将其保存在 ARC 和许多其他东西中，但没有任何效果对我有用。

我刚开始学习 Rust，但我仍然不太理解所有概念。

for data in settings.data {
        sched.add(
            tokio_cron_scheduler::Job::new_async(
                data.clone().schedule.as_str(),
                move |_, _| Box::pin(async {
                    println!("{}", data.name);
                }),
            ).unwrap()).await.unwrap();
    }

#[derive(Deserialize, Debug)]
pub struct Settings {
    pub data: Vec<Data>
}

#[derive(Deserialize, Debug, Clone)]
pub struct Data {
    pub name: String,
    pub schedule: String
}

这是错误

error: captured variable cannot escape `FnMut` closure body
  --> src\main.rs:30:29
   |
22 |       for data in settings.data {
   |           ---- variable defined here
...
30 |                   move |_, _| Box::pin(async {
   |  ___________________________-_^
   | |                           |
   | |                           inferred to be a `FnMut` closure
31 | |                     log::info!("starting job for task: {}", &data.name);
   | |                                                              ---- variable captured here
32 | |                 }),
   | |__________________^ returns a reference to a captured variable which escapes the closure body
   |
   = note: `FnMut` closures only have access to their captured variables while they are executing...
   = note: ...therefore, they cannot allow references to captured variables to escape

Answer 1

我们找到了一个可以使用的解决方案，尽管可以通过许多其他方式完成，但我们尝试在 for 中使用变量。

    for data in settings.data {
        let shared_data = std::sync::Arc::new(data);
        sched.add(
            tokio_cron_scheduler::Job::new_async(
                shared_data.clone().schedule.as_str(),
                 move |_, _| {
                     let data = shared_data.clone();
                     Box::pin(async move {
                         println!("{}", data.name);
                     })
                 },
            ).unwrap()).await.unwrap();
    }