text: const express = require('express')
  const webpackDevMiddleware = require('webpack-dev-middleware')
  const webpack = require('webpack')
  
  
  const config = require('./webpack.config.js')
  const compiler = webpack(config)
  // 实例化express示例
  const app = express();
  
  app.use(webpackDevMiddleware(compiler, {
      publicPath: config.output.publicPath
  }))
  
  app.listen(3001, () => {
      console.log('express server is running')
  })