我是 React 新手 我在我的 React 应用中使用带有 Babel 加载器的 Webpack

我的项目运行良好，直到我更换了机器，我复制了除 node_modules （使用 npm install 安装）之外的所有文件

当我尝试运行或构建项目时，它给了我错误，而这在旧机器上运行正常

import React from 'react';
import ReactDOM from 'react-dom';
import App from './app.js';
import {HashRouter,Route,Switch} from 'react-router-dom';
import '../node_modules/bootstrap/dist/css/bootstrap.css'


ReactDOM.render(
    <HashRouter>
        <App />
    </HashRouter>

, document.getElementById('app'));

Rs-MacBook-Pro:intra rd$ npm start

[email protected] start /Users/rd/Documents/intra webpack-dev-server --open --mode development

ℹ ｢wds｣: Project is running at http://localhost:8080/ ℹ ｢wds｣: webpack output is served from / ℹ ｢wds｣: Content not from webpack is served from /Users/rd/Documents/intra/public ℹ ｢wds｣: 404s will fallback to /index.html ℹ ｢wdm｣: wait until bundle finished: / ✖ ｢wdm｣: Hash: 53cc551e031b5ed39d70 Version: webpack 4.19.1 Time: 3596ms Built at: 2018-09-21 12:44:47 Asset Size Chunks Chunk Names bundle.js 836 KiB main [emitted] main Entrypoint main = bundle.js [./node_modules/ansi-html/index.js] 4.16 KiB {main} [built] [./node_modules/ansi-regex/index.js] 135 bytes {main} [built] [./node_modules/loglevel/lib/loglevel.js] 7.68 KiB {main} [built] [./node_modules/punycode/punycode.js] 14.3 KiB {main} [built] [./node_modules/url/url.js] 22.8 KiB {main} [built] [0] multi (webpack)-dev-server/client? http://localhost:8080 ./src/index.js 40 bytes {main} [built] [./node_modules/sockjs-client/dist/sockjs.js] 177 KiB {main} [built] [./node_modules/strip-ansi/index.js] 161 bytes {main} [built] [./node_modules/url/util.js] 314 bytes {main} [built] [./node_modules/webpack-dev-server/client/index.js? http://localhost:8080] (webpack)-dev-server/client? http://localhost:8080 7.78 KiB {main} [built] [./node_modules/webpack-dev-server/client/overlay.js] (webpack)-dev-server/client/overlay.js 3.58 KiB {main} [built] [./node_modules/webpack-dev-server/client/socket.js] (webpack)-dev-server/client/socket.js 1.05 KiB {main} [built] [./node_modules/webpack/hot sync ^./log$] (webpack)/hot sync nonrecursive ^./log$ 170 bytes {main} [built] [./node_modules/webpack/hot/emitter.js] (webpack)/hot/emitter.js 75 bytes {main} [built] [./src/index.js] 761 bytes {main} [built] [failed] [1 error] + 11 hidden modules

ERROR in ./src/index.js Module build failed (from ./node_modules/babel-loader/lib/index.js): SyntaxError: Unexpected token (9:4)

7 | 8 | ReactDOM.render(

9 | | ^ 10 | 11 | 12 |

@ multi (webpack)-dev-server/client? http://localhost:8080 ./src/index.js main 1 ℹ ｢wdm｣: Failed to compile.