vux和vux-loader安裝過(guò)后配置完啟動(dòng)報(bào)錯(cuò)Cannot find module 'vux-loader'，為什么？

var path = require('path')
var utils = require('./utils')
var config = require('../config')
var webpack = require("webpack")
var vueLoaderConfig = require('./vue-loader.conf')
function resolve (dir) {
return path.join(__dirname, '..', dir)
}

let originalConfig = {
entry: {

app: './src/main.js'

},
output: {

path: config.build.assetsRoot,
filename: '[name].js',
publicPath: process.env.NODE_ENV === 'production'
  ? config.build.assetsPublicPath
  : config.dev.assetsPublicPath

},
resolve: {

extensions: ['.js', '.vue', '.json', '.css'],
alias: {
  'vue$': 'vue/dist/vue.esm.js',
  '@': resolve('src')
}

},
module: {

rules: [
  {
    test: /\.vue$/,
    loader: 'vue-loader',
    options: vueLoaderConfig
  },
  {
    test: /\.js$/,
    loader: 'babel-loader',
    include: [resolve('src'), resolve('test')]
  },
  {
    test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,
    loader: 'url-loader',
    options: {
      limit: 10000,
      name: utils.assetsPath('img/[name].[hash:7].[ext]')
    }
  },
  {
    test: /\.(woff2?|eot|ttf|otf)(\?.*)?$/,
    loader: 'url-loader',
    options: {
      limit: 10000,
      name: utils.assetsPath('fonts/[name].[hash:7].[ext]')
    }
  }
]

},
plugins: [

new webpack.optimize.CommonsChunkPlugin('common.js'),
new webpack.ProvidePlugin({
  jQuery: "jquery",
  $: "jquery"
})

]
}
var vuxLoader = require('vux-loader')
var webpackConfig = originalConfig // 原來(lái)的 module.exports 代碼賦值給變量 webpackConfig
module.exports = vuxLoader.merge(webpackConfig, {
plugins: [

{
  name: 'vux-ui'
},
{
  name: 'duplicate-style'
}

]
})