Hyperapp#2 immutable state

example.js

'use strict' // Strict mode to throw mutation errors
import { h, app } from 'hyperapp'
import { immutable } from 'helpers'

// action that is trying to mutate the state
// will throw error for any mutation
const onclick = state => {
  ++state.counter
  return state
}

app({
  init: { counter: 0 },
  view: state => h('div', {}, [
    h('span', {}, state.counter),
    h('button', { onclick }, 'try to mutate!')
  ]),
  node: document.body
}, immutable)

immutable.js

const freeze = obj => {
  obj && Object.getOwnPropertyNames(obj).forEach(name =>
    typeof obj[name] == 'object' && freeze(obj[name]))
  return Object.freeze(obj)
}

export default dispatch => 
  (action, props, obj) => dispatch(
    typeof action == 'object' && !Array.isArray(action)
    ? freeze(action)
    : action,
    props,
    obj
  )