Common Lisp supports both dynamic and lexical scope. Emacs-like editors have been implemented in it, and there's no fundamental reason that a true Emacs couldn

Common Lisp supports both dynamic and lexical scope. Emacs-like editors have been implemented in it, and there's no fundamental reason that a true Emacs couldn't be. Scheme is more of a toy; I'd not prefer it to Common Lisp for a production system, whether that system is an OS or an editing environment.