reactjs - 编译react出现webpack语法错误

Question

我对带有 babel loader 和 eslint 的 webpack 有点陌生我正在尝试编译一个非常基本的应用程序我遇到了这个奇怪的语法错误，我无法弄清楚

这是我的index.js，我在其中遇到编译错误

const store = configureStore()

render(
  <Router>
    <Root store={ store } />
  </Router>,
  document.getElementById('console_root')
)

这是我得到的错误:

ERROR in ./src/index.js
Module build failed: SyntaxError: Unexpected token (19:2)

  17 |
  18 | render(
> 19 |   <Router>
     |   ^
  20 |     <Root store={ store } />
  21 |   </Router>,
  22 |   document.getElementById('console_root')

npm ERR! code ELIFECYCLE
npm ERR! errno 2

这是我的 webpack.config.js 文件

var webpack = require('webpack')
var path = require('path')

module.exports = {
  entry: {
    main: path.resolve(__dirname, 'src', 'index.js')
  },
  resolve: {
    extensions: ['*', '.js', '.jsx']
  },
  output: {
    path: path.resolve(__dirname, '..'),
    publicPath: '/',
    filename: 'bundle.js'
  },
  module: {
    rules: [
      {
        test: /\.(js|jsx)$/,
        exclude: /node_modules/,
        use: ['babel-loader', 'eslint-loader']
      },
      {
        test: /\.scss$/,
        use: ['style-loader', 'css-loader', 'sass-loader']
      }
    ]
  },
  plugins: [
    new webpack.optimize.UglifyJsPlugin({
      compress: {
        warnings: false
      }
    }),
    new webpack.DefinePlugin({
      'process.env': {
        NODE_ENV: '"production"'
      }
    })
  ]
}

这些是我的依赖项:

    "dependencies": {
    "material-ui": "^1.0.0-beta.26",
    "material-ui-icons": "^1.0.0-beta.17",
    "prop-types": "^15.6.0",
    "react": "^16.2.0",
    "react-dom": "^16.2.0",
    "react-redux": "^5.0.6",
    "react-router-dom": "^4.2.2",
    "redux": "^3.7.2"
  },
  "devDependencies": {
    "babel-core": "^6.26.0",
    "babel-eslint": "^8.1.2",
    "babel-loader": "^7.1.2",
    "css-loader": "^0.28.7",
    "eslint": "^4.14.0",
    "eslint-loader": "^1.9.0",
    "eslint-plugin-react": "^7.5.1",
    "react-scripts": "^1.0.17",
    "sass-loader": "^6.0.6",
    "style-loader": "^0.19.1",
    "webpack": "^3.10.0"
  }

有什么想法我做错了什么吗？

Answer 1

似乎您错过了将 react 预设添加到 webpack.config.js 文件或 .babelrc 中。

首先你应该安装它:npm i babel-preset-react --save-dev然后将 react 预设添加到您的 webpack 配置中，如下所示

  module: {
  rules: [
    {
      test: /\.js$/,
      exclude: /node_modules/,
      use: {
        loader: 'babel-loader',
        options: {
          presets: ['react']
        }
      }
    }
  ]
}

或者创建一个名为 .babelrc 的新文件并将其添加到其中

// .babelrc
{
  "presets": ["react"]
}

它应该适合你。