Running subprocess npm get me a error when creating ionic project - ionic-framework

Question

I just get this error when I try to lunch a new project on ionic 2.
I got a mkdir error, even by running the command on sudo, I use mac os.
I tried reinstall node, cordovan npm, tried to make some update, and googled the problem but can't find a solution.
Please help me, I'm an ionic beginner.
The error:
gyp ERR! configure error
gyp ERR! stack Error: EACCES: permission denied, mkdir '/Users/Loic/appIonic/swipeCard/test/node_modules/node-sass/build'
gyp ERR! System Darwin 17.7.0
gyp ERR! command "/usr/local/bin/node" "/Users/Loic/appIonic/swipeCard/test/node_modules/node-gyp/bin/node-gyp.js" "rebuild" "--verbose" "--libsass_ext=" "--libsass_cflags=" "--libsass_ldflags=" "--libsass_library="
gyp ERR! cwd /Users/Loic/appIonic/swipeCard/test/node_modules/node-sass
gyp ERR! node -v v10.10.0
gyp ERR! node-gyp -v v3.8.0
gyp ERR! not ok
Build failed with error code: 1
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! node-sass#4.9.0 postinstall: `node scripts/build.js`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the node-sass#4.9.0 postinstall script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR! /Users/Loic/.npm/_logs/2018-09-22T16_45_54_600Z-debug.log
[ERROR] An error occurred while running subprocess npm.
npm i exited with exit code 1.
Re-running this command with the --verbose flag may provide more information.
Thank

Answer 1

Try clearing the npm cache at C:\Users\\AppData\Roaming\npm-cache\

Answer 2

I was not using ionic for like six months. When i came back they asked me to update ionic to the latest version. After the update i can't even start a new project. So after wasting sometime i just downgraded to ionic 3.20.0 using the command
npm install -g cordova ionic#3.20.0
and now it's working fine