rearch

ReArch = re-imagined approach to application design and architecture

We must state definitions and provide for priorities and descriptions of data. We must state relationships, not procedures.

-- Grace Murray Hopper, Management and the Computer of the Future (1962)

Features

Specifically, ReArch is a novel solution to:

• ⚡️ State Management
• 🧮 Incremental Computation
• 🧱 Component-Based Software Engineering

And with those, come:

• Reactivity through declarative code

• Loose coupling and high testability

• App-level composability via a functional approach to dependency inversion

• Feature composition through side effects

In a Nutshell

Define your "capsules" (en-capsulated pieces of state) at the top level:

// Capsules are simply functions that consume a CapsuleHandle.
// The CapsuleHandle lets you get the state of other capsules,
// in addition to using a large variety of side effects.

// This capsule provides the count and a way to increment that count.
fn count_manager(CapsuleHandle { register, .. }: CapsuleHandle) -> (u8, impl CData + Fn()) {
    let (count, set_count) = register(effects::state::<Cloned<_>>(0));
    let increment_count = move || set_count(count + 1);
    (count, increment_count)
}

// This capsule provides the count, plus one.
fn count_plus_one_capsule(CapsuleHandle { mut get, .. }: CapsuleHandle) -> u8 {
    let (count, _increment_count) = get(count_manager);
    count + 1
}

let container = Container::new();

let ((count, increment_count), count_plus_one) =
    container.read((count_manager, count_plus_one_capsule));
assert_eq!(count, 0);
assert_eq!(count_plus_one, 1);

increment_count();

let ((count, _), count_plus_one) =
    container.read((count_manager, count_plus_one_capsule));
assert_eq!(count, 1);
assert_eq!(count_plus_one, 2);

Getting Started

Simply run: cargo add rearch rearch-effects

Then, create one container for your application:

use rearch::*;
use rearch_effects as effects;

fn main() {
  let container = Container::new();
  // Use the container.
}

And take a look at the examples to get an idea on how to make some of your own capsules!

Documentation

Also, there is some WIP documentation that will help you learn the core concepts behind ReArch!

Minimum Supported Rust Version (MSRV)

The MSRV of rearch is currently 1.75.0 and may change in any new ReArch version/release. The MSRV of other crates in this repo will be the latest stable release for the foreseeable future.

It is also worth mentioning that the example shown in "In a Nutshell" above requires nightly for unboxed_closures and fn_traits, which is feature-gated under the experimental-api feature. Once unboxed_closures and fn_traits stabilize, this nightly syntax will be the preferred syntax, and this will no longer be feature-gated. (Without nightly, you must instead call the slightly more verbose get.as_ref(some_capsule).clone() and register.register(effect()).)

Help Wanted!

As much as I have done with ReArch, it always seems like there is more to do. One person can only do so much!

If you would like to contribute, here are some areas where I would really appreciate help!

• Documentation (especially inline!)
  • If you could add code samples/improve clarity, that would be greatly appreciated.
• New side effects!
  • I've made many as I've needed them, but it'd be great to have more.
  • If you find yourself using a custom side effect over and over, consider making a PR! Chances are other developers can use it too.

Sponsors

You can become a sponsor of my work here!