$ cached_

Crate

Name: cached New version: 0.58.0 Release date: 2026-03-09T05:42:27.031439Z

Crate readme

Short description Caching structures and simplified function memoization

Long description cached provides implementations of several caching structures and macros for defining memoized functions with thread-safe caching, async support, and Redis integration.

Features • default • proc_macro • ahash • async • async_tokio_rt_multi_thread • redis_store • redis_smol • redis_tokio • redis_connection_manager • disk_store

Code Examples Basic usage

 use cached::proc_macro::cached;

#[cached]
fn fib(n: u64) -> u64 {
    if n == 0 || n == 1 { return n }
    fib(n-1) + fib(n-2)
}

Use an explicit cache-type

 use cached::proc_macro::cached;
use cached::SizedCache;

#[cached(
    ty = "SizedCache<String, usize>",
    create = "{ SizedCache::with_size(100) }",
    convert = r#"{ format!("{}{}", a, b) }"#
)]
fn keyed(a: &str, b: &str) -> usize {
    let size = a.len() + b.len();
    sleep(Duration::new(size as u64, 0));
    size
}

Only cache the initial function call

 #[once(time=10, option = true, sync_writes = true)]
fn keyed(a: String) -> Option<usize> {
    if a == "a" {
        Some(a.len())
    } else {
        None
    }
}

Cache results of an async function in redis

 #[io_cached(
    map_error = r##"|e| ExampleError::RedisError(format!("{:?}", e))"##,
    ty = "AsyncRedisCache<u64, String>",
    create = r##" {
        AsyncRedisCache::new("cached_redis_prefix", Duration::from_secs(1))
            .set_refresh(true)
            .build()
            .await
            .expect("error building example redis cache")
    } "##
)]
async fn async_cached_sleep_secs(secs: u64) -> Result<String, ExampleError> {
    std::thread::sleep(std::time::Duration::from_secs(secs));
    Ok(secs.to_string())
}

Cache results of a function on disk

 #[io_cached(
    map_error = r##"|e| ExampleError::DiskError(format!("{:?}", e))"##,
    disk = true
)]
fn cached_sleep_secs(secs: u64) -> Result<String, ExampleError> {
    std::thread::sleep(std::time::Duration::from_secs(secs));
    Ok(secs.to_string())
}

Links • https://crates.io/crates/cached • https://docs.rs/cached

https://docs.rs/cached

Release info

Release version: N/A

Release description N/A

Code Examples N/A