无法移出异步“Fn”闭包中捕获的变量

问：

这是我的代码。在这个程序中，我想创建一个简单的 websocket 服务器。当用户向 发送请求时，浏览器将与服务器建立 websocket 连接。ws://{url}/

use std::{collections::HashMap, sync::Arc};

use async_std::{prelude::*, sync::Mutex};
use tide_websockets::WebSocket;
use uuid::Uuid;

#[async_std::main]
async fn main() {
    let connections = Arc::new(Mutex::new(HashMap::new()));
    let mut app = tide::new();
    app.at("/").get(WebSocket::new(move |_, mut stream| async move {
        let uuid = Uuid::new_v4();

        // Add the connection to clients when opening a new connection
        connections.lock().await.insert(uuid, stream.clone());

        // Waiting for the connection to be closed
        while let Some(Ok(_)) = stream.next().await {}

        // Remove the connection from clients when it is closed
        connections.lock().await.remove(&uuid);

        Ok(())
    }));

    // app.bind(url).await
}

当我尝试编译这个程序时，rustc 说：

error[E0507]: cannot move out of `connections`, a captured variable in an `Fn` closure
  --> src/main.rs:11:57
   |
9  |       let connections = Arc::new(Mutex::new(HashMap::new()));
   |           ----------- captured outer variable
10 |       let mut app = tide::new();
11 |       app.at("/").get(WebSocket::new(move |_, mut stream| async move {
   |  ____________________________________--------------------_^
   | |                                    |
   | |                                    captured by this `Fn` closure
12 | |         let uuid = Uuid::new_v4();
13 | |
14 | |         // Add the connection to clients when opening a new connection
15 | |         connections.lock().await.insert(uuid, stream.clone());
   | |         -----------
   | |         |
   | |         variable moved due to use in generator
   | |         move occurs because `connections` has type `Arc<async_std::sync::Mutex<HashMap<Uuid, WebSocketConnection>>>`, which does not implement the `Copy` trait
...  |
23 | |         Ok(())
24 | |     }));
   | |_____^ move out of `connections` occurs here

For more information about this error, try `rustc --explain E0507`.
error: could not compile `mre` due to previous error

这是该方法的定义（不确定它是否有用）：Websocket::new

impl<S, H, Fut> WebSocket<S, H>
where
    S: Send + Sync + Clone + 'static,
    H: Fn(Request<S>, WebSocketConnection) -> Fut + Sync + Send + 'static,
    Fut: Future<Output = Result<()>> + Send + 'static,
{
    /// Build a new WebSocket with a handler function that
    pub fn new(handler: H) -> Self {
        Self {
            handler: Arc::new(handler),
            ghostly_apparition: PhantomData,
            protocols: Default::default(),
        }
    }

    // ...
}

在发布这个问题之前，我尝试搜索这个问题。大多数答案要么是无关紧要的，要么需要修改方法的源代码（这里是方法）。但是这个方法不是我写的，而是来自第三方的板条箱。还有什么方法可以解决这个问题吗？Websocket::new