I am logged in as admin user. I have installed latest node.js from https://nodejs.org/en/ using node-v6.9.1.pkg file. I have installed it for all users.
When I try to execute following command as given on ionic side (https://ionicframework.com/getting-started/):
npm install -g cordova ionic
npm ERR! Darwin 15.6.0
npm ERR! argv "/usr/local/bin/node" "/usr/local/bin/npm" "install" "-g" "cordova" "ionic"
npm ERR! node v6.9.1
npm ERR! npm v3.10.8
npm ERR! code MODULE_NOT_FOUND
npm ERR! Cannot find module 'github-url-from-git'
npm ERR! If you need help, you may report this error at:
npm ERR! <https://github.com/npm/npm/issues>
npm ERR! Please include the following file with any support request:
npm ERR! /Users/myusername/npm-debug.log
Seems that is a nodejs problem. Follow these steps:
1) rm -rf /usr/local/lib/node_modules/npm
2) reinstall nodejs