npm 安装yarn

一句命令搞定

  npm install -g yarn --registry=https://registry.npm.taobao.org
  
  
再配置下源

yarn config set registry https://registry.npm.taobao.org -g
yarn config set sass_binary_site http://cdn.npm.taobao.org/dist/node-sass -g

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再加入环境变量：setx path "%path%;C:\Users\Administrator\AppData\Local\Yarn\Data\global\node_modules\.bin"

参考： https://www.jianshu.com/p/9327d5544335