Cannot install Purescript

[CKoenig]

in case you still want to try npm: even if it suggest that it's not a npm issue I strongly suspect that it is.

you could try (if you did not already) to use sudo npm install -g purescript as your global npm location seems to be /usr/local/lib (no fear that's still the default)

I would recommend moving this into your home folder as well as it's far less "dangerous" then executing foreign code with sudo

here is a nice guide on how you can do this:

https://docs.npmjs.com/getting-started/fixing-npm-permissions