import { observable } from 'mobx';
import { observer } from 'mobx-react';
import React from 'react'
import {render} from 'react-dom'

const state = { n: 0 };
const incr = () => state.n++;
const decr = () => state.n--;

const view = observer(() => 
  <div>
    <h1>{state.n}</h1>
    <button onclick={incr}>+</button>
    <button onclick={decr}>-</button>
  </div>)

render(
  <view />,
  document.querySelector('#app')
);