content: import React from 'react'
  import ReactDom from 'react-dom'
  import App from './app.jsx'
  
  console.log('client = ', client, typeof client)
  console.log('client.publicPath = ', client.publicPath)
  console.log('debug = ' + debug, typeof debug)
  console.log('array1 = ', array1)
  
  let arr = [1, 2, 3]
  let copyArr = [...arr]
  console.log('test es6 syntax: ', copyArr)
  
  let filed = {
    a: 1,
    b: 2
  }
  let obj = {
    ...filed
  }
  console.log('test es6 syntax: ', obj)
  
  ReactDom.render(<App />, document.querySelector('#react-app'))
  