pg uses vi, see: http://www.paulgraham.com/pfaq.html http://www.paulgraham.com/pfaq.html. Others do Lisp in a variety of IDEs. I prefer Emacs, but it is not t

pg uses vi, see: http://www.paulgraham.com/pfaq.html http://www.paulgraham.com/pfaq.html. Others do Lisp in a variety of IDEs. I prefer Emacs, but it is not the only option.