anchor.diff: +  ;; C
  +  ;; C
     ;; Defines the greater-than operator
   (define (> a b) (if (< a b) nil T))
   (define (abs x) (if (< x 0) (- 0 x) x))
  
positive.code:   (if (> 1 n)
      1
      (+ (fib (- n 1)) (fib (- n 2))))) 
  
negative.code: 
  ;; Usage: (when (< x 2) (set! x 2)) ??
  (defmacro (when condition . body)
      `(if ,condition
         (progn ,@body)
         nil))
  
  (defmacro (unless condition . body)
      `(if ,condition 
         nil 
         (progn ,@body)))
  
  (defmacro (cond-list clauses)
      (clauses))
  
  ;    `(if ,test 
  ;       (progn ,@forms)
  ;       (cond ,@(cdr clauses)))))
  
  (define (cond . clauses)
    (cond-list clauses))
  
  (defmacro (for-each fn seq)
    `(progn (map nil ,fn ,seq) t))
  
  (defmacro (and-list body)
    `(if ,body
  