Fuchsia中Rust 开发的示例分析

pub struct KeyValueStore<U>        where U: Hash + Eq + Send + 'static{        inner_store: HashMap<U, String>,        self_actor: Option<KeyValueStoreActor<U>>,    }impl<U: Hash + Eq + Send + 'static> KeyValueStore<U> {        pub fn new() -> Self {                Self {                        inner_store: HashMap::new(),                        self_actor: None,                }    }}// All methods in this block form our Actor's API#[derive_actor]impl<U: Hash + Eq + Send + 'static> KeyValueStore<U> {        pub fn query(&self, key: U, f: Box<dyn Fn(Option<String>) + Send + 'static>) {                println!("query");                f(self.inner_store.get(&key).map(String::from))     }    pub fn set(&mut self, key: U, value: String) {                println!("set");                self.inner_store.insert(key, value);    }}#[tokio::main]async fn main() {    let (kv_store, handle) = KeyValueStoreActor::new(KeyValueStore::new()).await;            // We can use an async API that's typed and nominal        kv_store.query("foo", Box::new(|value| println!("before {:?}", value))).await;        kv_store.set("foo", "bar".to_owned()).await;        kv_store.query("foo", Box::new(|value| println!("after {:?}", value))).await;    // We must drop any references to kv_store before we await the handle, or it will leak!    drop(kv_store);        handle.await;    }AI代码助手复制代码