设置http代理
npm config set proxy=http://127.0.0.1:1080
取消代理
npm config delete proxy
npm设置淘宝镜像
npm config set registry=https://registry.npm.taobao.org
npm取消淘宝镜像
npm config delete registry
查看代理信息（当前配置）
npm config list
sass
安装
npm install --save-dev node-sass
npm install --save-dev sass-loader
sass-loader版本过高运行错误TypeError: this.getOptions is not a function
npm install -S sass-loader@10.x
卸载
npm uninstall --save-dev node-sass
npm uninstall --save-dev sass-loader