Common Lisp Overview

Common Lisp (ANSI standard, 1994) unified the MacLisp descendants. It's a large, industrial-strength, multi-paradigm language with CLOS (a powerful object system with multiple dispatch), the condition system (restarts), macros, native compilation (SBCL produces fast machine code), image-based development, and an extremely stable standard: decades-old code still runs.

Implementations: SBCL, CCL, ECL, ABCL (JVM), CLISP, LispWorks, Allegro CL, Clasp (LLVM/C++ interop).

👉 See the companion Common Lisp course on this site for full coverage.

(defun fizzbuzz (n)
  (loop for i from 1 to n
        do (format t "~a~%"
                   (cond ((zerop (mod i 15)) "FizzBuzz")
                         ((zerop (mod i 3)) "Fizz")
                         ((zerop (mod i 5)) "Buzz")
                         (t i)))))

(defclass animal ()
  ((name :initarg :name :accessor name)))
(defgeneric speak (a))
(defmethod speak ((a animal)) (format nil "~a makes a sound" (name a)))

(handler-case (/ 1 0)
  (division-by-zero () "can't divide by zero"))