minimum redux implimentation

index.js

import {element, createApp} from 'deku'

function action() {
  return {
    type: 'CLICKED'
  }
}

function reducer(state, action) {
  switch(action.type) {
    case 'CLICKED':
      return state
  }
}

function createStore(reducer, initialState = {}) {
  let currentState = initialState
  let listeners = []

  let dispatch = (action) => {
    currentState = reducer(currentState, action)
    for(var i = 0, listener; listener = listeners[i]; i++) {
      listener()
    }
  }

  let subscribe = (func) => {
    listeners.push(func)

    return function unsubscribe() {
      const i = listeners.indexOf(func)
      listeners.splice(index, 1)
    }
  }

  let getState = () => {
    return currentState
  }

  return { dispatch, subscribe, getState }
}

let store = createStore(reducer)

let render = createApp(document.body, store.dispatch)

let App = {
  render({ dispatch }) {
    return (
      <div onClick={dispatch(action())}>hello</div>
    )
  }
}

function main() {
  render(
    <App />,
    store.getState()
  )
}

main()
store.subscribe(main)