PRINCIPLES OF PROGRAMMING LANGUAGES:
			COMMON LISP VS. SCHEME

	   Gary T. Leavens, Department of Computer Science,
	   Iowa State University, Ames, Iowa 50011-1040 USA
			leavens@cs.iastate.edu
		     $Date: 1998/09/15 20:00:32 $

The table below highlights the important differences between
Common Lisp and Scheme for those that know a more standard
Lisp dialect.  Only the differences are highlighted here,
there are many more similarities.

Common Lisp                     Scheme
-------------------------------------------------------
()	; eq to nil		()
nil			        #f
t			        #t

(eq x y)                        (eq? x y)
(equal x y)                     (equal? x y)

(atom x)                        (not (pair? x))
(consp x)                       (pair? x)
(null x)                        (null? x)
(symbolp x)                     (symbol? x)
(zerop x)                       (zero? x)

(setf (car x) y)		(set-car! x y)
(setf (cdr x) y)		(set-cdr! x y)

(mapcar #'f l)                  (map f l)
(map 'list #'f l)		(map f l)

(mapcar #'(lambda (x) (g x)) l) (map (lambda (x) (g x)) l)

#'(lambda (x) y)                (lambda (x) y)
(lambda (x) y) ; in ANSI CL     (lambda (x) y)

(setq var y)                    (set! var y)
(setf var y)                    (set! var y)

(cond                           (cond
  ((null x) 0)                    ((null? x) 0)
  ((eq x y) (f x))                ((eq? x y) (f x))
  (t (g y)))                      (else (g y)))

(defun square (x)               (define (square x)
  (* x x))                        (* x x))
				; or
				(define square (lambda (x) (* x x)))

(funcall (g f) x)		((g f) x)

(defun compose (f g)            (define (compose f g)
  #'(lambda (x)                    (lambda (x)
      (funcall f                      (f (g x))))
        (funcall g x))))

(defun my-cadr (ls)             (define my-cadr (ls)
  (funcall                        ((compose car cdr)
   (compose #'car #'cdr)            ls))
   ls))


Acknowledgments

Thanks to Erik Naggum, Richard Gabriel, and Barry Margolin for correcting
my ancient Lisp accent.  Of course any errors are not their responsibility
but mine.