anchor.diff:        (terpri))))
   
   (defun sys.int::%invalid-argument-error (&rest args)
  -  (fresh-line)
  -  (write-string "Invalid arguments to function")
  -  (fresh-line)
  -  (backtrace)
  -  (loop))
  +  (error "Invalid arguments to function."))
   
   (defun copy-list (list)
     (when list
  
positive.code: (write-to-the-screen "Hello, World!")
  
  (defun sys.int::raise-undefined-function (invoked-through)
    (error 'undefined-function :name symbol))
  
  (defun sys.int::raise-unbound-error (symbol)
    (error 'unbound-variable :name symbol))
  
negative.code: (defun endp (list)
    (cond ((null list) t)
          ((consp list) nil)
  