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https://github.com/jnorth/megalith

The small and straightforward JavaScript state container.
https://github.com/jnorth/megalith

flux react state-container

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The small and straightforward JavaScript state container.

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Megalith


The small and straightforward JavaScript state container.

Megalith allows you to arrange your application state into a nested tree of
`Store` objects, each encapsulating related state and actions. It can be
considered an implementation of ideas from Redux and mobx-state-tree, with a
lightweight class-based API.

## Overview

Megalith has the same three core concepts as many other state containers:

> 1. Application state is stored in a single object tree.

> 2. You mark your intent to change state by dispatching actions. Actions are
> simple objects with a `type` and optionally some parameters.

> 3. Given an action and the previous state, a new state tree is generated using
> a simple function.

The implementation differs however, with actions being created automatically
from `action` methods and state being organized into a tree of `Store` classes.
This allows you to retain most benefits from a more functional approach, while
reducing boilerplate and keeping related code together.

## Example

```js
import { Store, action, snapshot } from 'megalith';

class App extends Store {
// Set our store's initial state. This defines its 'shape' and default values.
initialState = {
counter: 0,
messages: new MessagesStore(), // Stores can be nested.
};

// Action methods are the only way to change store state. They can be called
// like regular methods, and are expected to return a modified copy of the
// entire state object.
@action increment(n=1) {
return { ...this.state, counter: this.counter + n };
}
}

class MessagesStore extends Store {
// Store state is typically an object, but can be an array, string, number,
// or any other type of data.
initialState = [];

@action add(message) {
return [...this.state, message];
}
}

const app = new App();

// State properties can be accessed like regular (read-only) properties.
app.counter; // => 0

// Action methods are called like regular methods.
app.increment(5);
app.messages.add('hello world!');

// Action methods trigger events
app.events.all(event => {
event.action; // => { type: 'messages.add', payload: ['hello world!'] }

// Snapshots of the entire state tree can be taken at any point.
snapshot.create(event.store); // => { counter: 5, messages: ['hello world!'] }
});
```

## Documentation

- [Quick Start](/docs/quick-start)
- [Introduction](/docs/quick-start/1-introduction.md)
- [State](/docs/quick-start/2-state.md)
- [Actions](/docs/quick-start/3-actions.md)
- [Events](/docs/quick-start/4-events.md)

- [API Reference](/docs/api)
- [Store](/docs/api/Store.md)
- [action](/docs/api/action.md)
- [events](/docs/api/events.md)
- [snapshot](/docs/api/snapshot.md)

- [Examples](/docs/examples)
- [Async Actions](/docs/examples/async-actions.md)
- [ES5 Syntax](/docs/examples/es5.md)

## License

Copyright (c) 2016 Joseph North

Megalith is licensed under the [MIT License](LICENSE.md).