I tried all that multiple times and still getting the same errors as the author.
npm ERR! ionic@2.0.0-beta.17 postinstall: node lib/tasks/postinstall
npm ERR! Exit status 8
npm ERR!
npm ERR! Failed at the ionic@2.0.0-beta.17 postinstall script ‘node lib/tasks/postinstall’.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the ionic package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR! node lib/tasks/postinstall
npm ERR! You can get information on how to open an issue for this project with:
npm ERR! npm bugs ionic
npm ERR! Or if that isn’t available, you can get their info via:
npm ERR! npm owner ls ionic
npm ERR! There is likely additional logging output above.
npm ERR! Darwin 15.3.0
npm ERR! argv “node” “/usr/local/bin/npm” “i” “-g” "ionic@beta"
npm ERR! node v0.10.42
npm ERR! npm v3.6.0
npm ERR! path npm-debug.log.792550016
npm ERR! code EACCES
npm ERR! errno 3
Is node 0.10.42 not high enough? Also: is it best practise to install with sudo or without?