1. var webpack = require('webpack');
    
  2. 
    
  3. module.exports = {
    
  4.   context: __dirname,
    
  5.   entry: './app.js',
    
  6.   module: {
    
  7.     loaders: [
    
  8.       {
    
  9.         loader: require.resolve('babel-loader'),
    
  10.         test: /\.js$/,
    
  11.         exclude: /node_modules/,
    
  12.         query: {
    
  13.           presets: [
    
  14.             require.resolve('@babel/preset-env'),
    
  15.             require.resolve('@babel/preset-react'),
    
  16.           ],
    
  17.           plugins: [require.resolve('@babel/plugin-proposal-class-properties')],
    
  18.         },
    
  19.       },
    
  20.     ],
    
  21.   },
    
  22.   plugins: [
    
  23.     new webpack.DefinePlugin({
    
  24.       'process.env': {
    
  25.         NODE_ENV: JSON.stringify('development'),
    
  26.       },
    
  27.     }),
    
  28.   ],
    
  29.   resolve: {
    
  30.     alias: {
    
  31.       react: require.resolve('react'),
    
  32.     },
    
  33.   },
    
  34. };