ReactNative坑

npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/mkdirp
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/mute-stream
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/ncp
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/path-is-absolute
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/pkginfo
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/read
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/revalidator
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/stack-trace
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/strip-ansi
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/supports-color
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/winston
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/wrappy
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/once
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/inflight
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/glob
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/rimraf
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/utile
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/chalk
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/minimist
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/prompt
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules/react-native-cli/node_modules/semver
npm ERR! path /usr/local/lib/node_modules/react-native-cli/node_modules/mkdirp
npm ERR! code ENOENT
npm ERR! errno -2
npm ERR! syscall access
npm ERR! enoent ENOENT: no such file or directory, access '/usr/local/lib/node_modules/react-native-cli/node_modules/mkdirp'
npm ERR! enoent This is related to npm not being able to find a file.
npm ERR! enoent 

npm ERR! A complete log of this run can be found in:
npm ERR!     /Users/yaohongliang/.npm/_logs/2018-07-07T07_41_42_332Z-debug.log

今天在安装RN的字体图标的时候，安装不上，就乱搞版本，动这动那到最后Demo都跑步起来，也不能重新建项目了。报了以上的错误。
解决办法

sudo npm cache clean -f

sudo npm install -g n

sudo n stable

清理一下缓存吧。就发现可以了。虚惊一场。。。