解决webpack -p压缩打包react报语法错误的方法

var webpack = require('webpack');
//打包less插件
var ExtractTextPlugin = require('extract-text-webpack-plugin');
//这里的'./css/bundle.css'设置打包地址
var ExtractLess = new ExtractTextPlugin('./css/bundle.css');
//打包多个文件插件
//var commonsPlugin = new webpack.optimize.CommonsChunkPlugin('common.js');
var path = require('path');
module.exports = {
 entry:[
  './reactDom/index.js'
 ],
 output:{
  path:'./build',
  filename:'indexReact.js'
 },
 module:{
  loaders:[
   {test: /\.js$/, exclude: /(node_modules|bower_components)/, loader: 'babel',query:{presets:['es2015','react']}},
   {test:/\.less$/,loader:ExtractTextPlugin.extract("style-loader", "css-loader!less-loader")},
   //图片文件使用 url-loader 来处理，小于8kb的直接转为base64
   { test: /\.(png|jpg)$/, loader: 'url-loader?q=8192'}

  ]
 },
 resolve:{
  extensions:['','.js']
  },

 plugins:[
  ExtractLess,
  
 ]
};

 plugins:[
  new webpack.optimize.UglifyJsPlugin({
   compress:{
    warnings:false
   },
   mangle:{
    except:['$super','$','exports','require']
   }
  })
 ]