今天使用vue-cli，明明写的没错，都是vue-cli自动生成的，编译时怎嘛就会报错呢？
报错信息如下：
浏览器端报错：
Failed to compile. ./src/components/Hi1.vue Module not found:
Error: Can't resolve 'stylus-loader' in 'E:desktopvue-reviewvuejsvue-clivueclisrccomponents' @ ./src/components/Hi1.vue 4:2-310 @ ./src/router/index.js @ ./src/main.js @ multi (webpack)-dev-server/client?http://localhost:8080 webpack/hot/dev-server ./src/main.js
控制台报错：
These dependencies were not found:
* !!vue-style-loader!css-loader?{"sourceMap":true}!../../node_modules/vue-loader/lib/style-compiler/index?{"vue":true,"id":"data-v-3232a8d1","scoped":true,"hasInlineConfig":false}!stylus-loader?{"sourceMap":true}!../../node_modules/vue-loader/lib/selector?type=styles&index=0!./Hi2.vue in ./src/components/Hi2.vue
* !!vue-style-loader!css-loader?{"sourceMap":true}!../../node_modules/vue-loader/lib/style-compiler/index?{"vue":true,"id":"data-v-32249150","scoped":true,"hasInlineConfig":false}!stylus-loader?{"sourceMap":true}!../../node_modules/vue-loader/lib/selector?type=styles&index=0!./Hi1.vue in ./src/components/Hi1.vue
To install them, you can run: npm install --save !!vue-style-loader!css-loader?{"sourceMap":true}!../../node_modules/vue-loader/lib/style-compiler/index?{"vue":true,"id":"data-v-3232a8d1","scoped":true,"hasInlineConfig":false}!stylus-loader?{"sourceMap":true}!../../node_modules/vue-loader/lib/selector?type=styles&index=0!./Hi2.vue !!vue-style-loader!css-loader?{"sourceMap":true}!../../node_modules/vue-loader/lib/style-compiler/index?{"vue":true,"id":"data-v-32249150","scoped":true,"hasInlineConfig":false}!stylus-loader?{"sourceMap":true}!../../node_modules/vue-loader/lib/selector?type=styles&index=0!./Hi1.vue
原来vue-cli在初始化项目时在package.json中没有引入 stylus和stylus-loader，而我在写代码时有用vscode的自动提示功能，然后就导致了错误的代码出现，（其实也不算错误，但我还是这么叫它）
<style lang="stylus" scoped>
</style>
就因为代码提示自动生成的lang="stylus",巧了，vue-cli初始化就没这方面的包
只要在项目根目录下运行：npm install stylus stylus-loader --save-dev,在停止vue-cli，重新npm run dev一下就ok了（如果过改了package.json里的dev，可能不是这个命令运行vue-cli）
有时候太图方便也不好，尤其是在不了解它时o(╥﹏╥)o