fix node+npm
npm i -g npm
error: $ npm install -g idyll npm WARN deprecated nomnom@1.6.2: Package no longer supported. Contact support@npmjs.com for more info. /usr/local/bin/idyll -> /usr/local/lib/node_modules/idyll/bin/idyll.js npm WARN acorn-dynamic-import@4.0.0 requires a peer of acorn@^6.0.0 but none is installed. You must install peer dependencies yourself.
brew update xcrun: error: invalid active developer path
sudo xcode-select --install
and reinstall node+npm, see sources
soures: https://gist.github.com/TonyMtz/d75101d9bdf764c890ef https://stackoverflow.com/questions/11177954/how-do-i-completely-uninstall-node-js-and-reinstall-from-beginning-mac-os-x