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rustHow to use an async Rust HashMap?


An async Rust HashMap is a concurrent data structure that allows multiple threads to access and modify the same data without blocking each other. It is a type of concurrent hash table that is optimized for concurrent access.

Example code

use async_std::sync::{Arc, RwLock};

let map = Arc::new(RwLock::new(HashMap::new()));

// Insert a key-value pair
map.write().await.insert("key", "value");

// Get a value
let value = map.read().await.get("key");

Output example

Some("value")

Code explanation

  1. use async_std::sync::{Arc, RwLock};: This imports the Arc and RwLock modules from the async_std library, which are used to create a thread-safe reference-counted pointer and a read-write lock respectively.

  2. let map = Arc::new(RwLock::new(HashMap::new()));: This creates a new thread-safe reference-counted pointer to a new empty HashMap.

  3. map.write().await.insert("key", "value");: This acquires a write lock on the HashMap and inserts a key-value pair.

  4. let value = map.read().await.get("key");: This acquires a read lock on the HashMap and retrieves the value associated with the given key.

Helpful links

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