plait

Plait

A minimal JavaScript framework for building reactive web components. Heavily inspired by The Elm Architecture and Elm's StartApp.

The Idea

I've been impressed with the experience of writing reactive apps in Elm. I wanted to find a way to achieve a similar architecture with a minimal amount of vanilla JavaScript.

In Plait, an app is composed of one or more encapsulated components. Each component implements view, which renders the component with a given state; update, which updates the state based on a given action; and init, which provides the initial state.

State is implemented as an immutable Map, and is contained & managed with redux. Components render their views with virtual-dom, with DOM events being transparently handled by dom-delegator.

Note: It's possible to write views in JSX and compile them to JS using jsx-transform (with factory: 'h'). See below for an example.

An Example Application

The following is an example of an application composed of a single counter component.

import h from 'virtual-dom/h'
import { App } from 'plait'

const appNode = App.start({ init, update, view })

document.getElementById('app').appendChild(appNode)

function init () {
  return {
    count: 0
  }
}

function update (state, action) {
  switch (action.type) {
    case 'DECREMENT':
      return state.update('count', x => x - 1)

    case 'INCREMENT':
      return state.update('count', x => x + 1)
  }
}

function view (state, dispatch) {
  return (
    <div>
      <button ev-click={dispatch({ type: 'DECREMENT' })}>-</button>
      <span>{state.get('count')}</span>
      <button ev-click={dispatch({ type: 'INCREMENT' })}>+</button>
    </div>
  )
}

License

The MIT License (MIT)

Copyright (c) 2016 Joseph Wynn

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.