带有 babel-loader 的 Webpack 无法识别 import 关键字

Question

我有这个webpack.config.js:

module.exports = {
  entry: './src/admin/client/index.jsx',
  output: {
    filename: './src/admin/client/static/js/app.js'
  },
  loaders: [
    {
      test: /\.jsx?$/,
      loader: 'babel',
      exclude: /node_modules/,
      query: {
        optional: ['runtime']
      }
    }
  ],
  resolve: {
    extensions: ['', '.js', '.jsx']
  }
};

...但我仍然收到此错误：

$ webpack -v
Hash: 2a9a40224beb025cb433
Version: webpack 1.10.5
Time: 44ms
   [0] ./src/admin/client/index.jsx 0 bytes [built] [failed]

ERROR in ./src/admin/client/index.jsx
Module parse failed: /project/src/admin/client/index.jsx Line 1: Unexpected reserved word
You may need an appropriate loader to handle this file type.
| import React from 'react';
| import AdminInterface from './components/AdminInterface';

我有：

全局和本地安装webpack
已安装 babel-loader、babel-core 和 babel-runtime
已在全球范围内安装 babel-loader，以防万一

为什么 webpack 似乎忽略了 babel-loader？还是 babel-loader 不适用于模块？

更新:

看起来 babel 可以很好地处理输入文件。当我运行:

./node_modules/babel/bin/babel.js ./src/admin/client/index.jsx

...它按预期输出 ES5。因此，在我看来 webpack 没有正确加载 babel-loader.

Answer 1

这看起来像是操作失误的情况。我的 webpack.config.js 结构不正确。具体来说，我需要将加载器详细信息放在 module 部分中：

module.exports = {
  entry: './src/admin/client/index.jsx',
  output: {
    filename: './src/admin/client/static/js/app.js'
  },
  module: {
    loaders: [
      {
        test: /\.jsx?$/,
        loader: 'babel',
        exclude: /node_modules/,
        query: {
          optional: ['runtime']
        }
      }
    ],
    resolve: {
      extensions: ['', '.js', '.jsx']
    }
  }
};

Answer 2

我通过包含 es2015 和 react presets 然后添加解决了同样的问题他们到 webpack.config.js 文件。

npm install --save-dev babel-preset-es2015 npm install --save-dev babel-preset-react

如本 post 中所述：https://www.twilio.com/blog/2015/08/setting-up-react-for-es6-with-webpack-and-babel-2.html

我的完整 webpack.config.js 文件：

module.exports = {
  context: __dirname + "/src",
  entry: './main',
  output: {
    path: __dirname + "/build",
    filename: "bundle.js"
  },
  module: {
    loaders: [
      { 
        test: /\.js$/,
        exclude: /node_modules/,
        loader: "babel-loader",
        query: {
          presets: ['es2015', 'react']
        }
      }
    ],
    resolve: {
      extensions: ['.js', '.jsx']
    }
  }
};

Answer 3

你的babel是什么版本的？如果babel版本是6+以上，你需要像这样识别预设'es2015'和'react'

module: {
  loaders: [
    {
      test: /\.jsx?$/,
      exclude: /(node_modules|bower_components)/,
      loader: 'babel', // 'babel-loader' is also a legal name to reference
      query: {
        presets: ['react', 'es2015']
      }
    }
  ]
}

不要忘记安装这些模块：

npm install babel-loader babel-core babel-preset-es2015 babel-preset-react --save-dev

带有 babel-loader 的 Webpack 无法识别 import 关键字

Webpack with babel-loader not recognizing import keyword

javascript

ecmascript-6

webpack

babeljs

transpiler