yarn安装时报错如下：

[1/5] Validating package.json...
[2/5] Resolving packages...
[3/5] Fetching packages...
info There appears to be trouble with your network connection. Retrying...
info There appears to be trouble with your network connection. Retrying...
info There appears to be trouble with your network connection. Retrying...
info There appears to be trouble with your network connection. Retrying...
原因可能是yarn没有权限。

安装时用管理员身份安装即可。

Windows下用 PowerShell(管理员) 安装即可。

npm install yarn -g