atomic_struct

atomic_struct is a Rust proc-macro that allows you to create structs with atomic, asynchronous fields. Each field is automatically wrapped in an AtomicMember<T> (Arc<Mutex<T>), providing thread-safe async access to individual fields.

Features

• #[atomic_struct] attribute macro for easy struct creation
• Each field is wrapped in AtomicMember<T>
• Automatically generated new() constructor
• Async getter/setter for each field
• Cloneable atomic fields
• Optional: Serde field attributes are preserved (#[serde(...)])

Installation

Add the crate to your Cargo.toml:

[dependencies]
atomic_struct = { path = "../atomic_struct" }  # or crates.io version when published
tokio = { version = "1", features = ["macros", "rt-multi-thread"] }

Examples

use atomic_struct::atomic_struct;

#[atomic_struct]
struct AppState {
    counter: i32,
    name: String,
}

#[tokio::main]
async fn main() {
    let state = AppState::new(0, "init".to_string());

    // Async setters
    state.counter.set(42).await;
    state.name.set("hello".to_string()).await;

    // Async getters
    println!("Counter: {}", state.counter.get().await);
    println!("Name: {}", state.name.get().await);

    // Clone a single field
    let counter_clone = state.counter.clone();
    counter_clone.set(99).await;
    println!("Counter after clone: {}", state.counter.get().await);
}

Advanced Usage

Serde Support

If you add Serde field attributes like #[serde(rename = "…")] or #[serde(skip)] to the original fields, they will automatically be preserved.

#[atomic_struct]
struct AppState {
    #[serde(rename = "cnt")]
    counter: i32,
    #[serde(skip)]
    name: String,
}

Global Singleton Usage

atomic_struct structs can be safely stored in Arc or OnceCell:

use once_cell::sync::OnceCell;
static GLOBAL_STATE: OnceCell<AppState> = OnceCell::new();

Benefits

• Thread-safe and async by default
• Minimal boilerplate
• Cloneable fields for parallel tasks
• Automatic getters and setters