lisp command interpreter

 rep is a dialect of Lisp, designed to be used both as an extension
 language for applications and as a general purpose programming language.
 .
 It was originally written to be mostly-compatible with Emacs Lisp, but has
 subsequently diverged markedly. Its aim is to combine the best features of
 Scheme and Common Lisp and provide an environment that is comfortable for
 implementing both small and large scale systems. It tries to be a
 "pragmatic" programming language.