It has an input method that lets you type the non ASCII characters more easily. The default uses the super key (windows key) like alt uses alt, bit there's also a mode that allows you to prefix things with ., So e.g. to get rho you type .r, and to get an actual . you type .., which I find more ergonomic. And you can launch the repl from inside emacs as well. I'm mostly a vim user myself, and have been using it with spacemacs for a more familiar experience.