Crate rsactor_derive 

Derive macros for rsActor framework

This crate provides derive macros for the rsActor framework, allowing users to automatically implement common traits with sensible defaults.

Actor Derive Macro

The #[derive(Actor)] macro provides a convenient way to implement the Actor trait for simple structs and enums that don’t require complex initialization logic.

Generated Implementation

When you use #[derive(Actor)], it generates:

• Args type set to Self (the struct or enum itself)
• Error type set to std::convert::Infallible (never fails)
• on_start method that simply returns the provided args

Usage

With Structs

use rsactor::Actor;

#[derive(Actor)]
struct MyActor {
    name: String,
    count: u32,
}

With Enums

use rsactor::Actor;

#[derive(Actor)]
enum StateActor {
    Idle,
    Processing(String),
    Completed(i32),
}

This is equivalent to manually writing:

use rsactor::{Actor, ActorRef};
use std::convert::Infallible;

impl Actor for MyActor {
    type Args = Self;
    type Error = Infallible;

    async fn on_start(
        args: Self::Args,
        _actor_ref: &ActorRef<Self>,
    ) -> std::result::Result<Self, Self::Error> {
        Ok(args)
    }
}

When to Use

Use the derive macro when:

• Your actor doesn’t need complex initialization
• You want to pass a fully constructed instance to spawn()
• You don’t need custom error handling during initialization

For complex initialization (async resource setup, validation, etc.), implement the Actor trait manually.

Message Handlers Attribute Macro

The #[message_handlers] attribute macro combined with #[handler] method attributes provides an automated way to generate Message trait implementations and register message handlers.

Usage

use rsactor::{Actor, ActorRef, message_handlers};

#[derive(Actor)]
struct MyActor {
    count: u32,
}

struct Increment;
struct GetCount;

#[message_handlers]
impl MyActor {
    #[handler]
    async fn handle_increment(&mut self, _msg: Increment, _: &ActorRef<Self>) -> u32 {
        self.count += 1;
        self.count
    }

    #[handler]
    async fn handle_get_count(&mut self, _msg: GetCount, _: &ActorRef<Self>) -> u32 {
        self.count
    }

    // Regular methods without #[handler] are left unchanged
    fn internal_method(&self) -> u32 {
        self.count * 2
    }
}

Benefits

• Automatic generation of Message<T> trait implementations
• Selective processing: only methods with #[handler] attribute are processed
• Reduced boilerplate and potential for errors
• Type-safe message handling with compile-time checks

Attribute Macros

message_handlers

Attribute macro for automatically generating Message trait implementations from method definitions.

Derive Macros

Actor

Derive macro for automatically implementing the Actor trait.