2. Lather, Rinse, Repeat: A Tour of the REPL

In this chapter you’ll set up your programming environment and write your first Common Lisp programs. We’ll use the easy-to-install Lisp in a Box developed by Matthew Danish and Mikel Evins, which packages a Common Lisp implementation with Emacs, a powerful Lisp-aware text editor, and SLIME,1 a Common Lisp development environment built on top of Emacs.

This combo provides a state-of-the-art Common Lisp development environment that supports the incremental, interactive development style that characterizes Lisp programming. The SLIME environment has the added advantage of providing a fairly uniform user interface regardless of the operating system and Common Lisp implementation you choose. I’ll use the Lisp in a Box environment in order to have a specific development environment to talk about; folks who want to explore other development environments such as the graphical integrated development environments (IDEs) provided by some of the commercial Lisp vendors or environments based on other editors shouldn’t have too much trouble translating the basics.2