anchor.diff:                    (with-ps-gensyms (n)
                       (let ((decls nil) (assigns nil) (defaults nil))
                         (mapc (lambda (k)
  -                              (multiple-value-bind (var init-form keyword-str)
  +                              (multiple-value-bind (var init-form keyword-str suppl)
                                     (parse-key-spec k)
                                   (push `(var ,var) decls)
                                   (push `(,keyword-str (setf ,var (aref arguments (1+ ,n)))) assigns)
  -                                (push (list 'defaultf var init-form) defaults)))
  +                                (push (list 'defaultf var init-form suppl) defaults)))
                               (reverse keys))
                         `(,@decls
                           (loop :for ,n :from ,(length requireds)
  
positive.code:                      (mapcar #'parse-optional-spec optionals))))
             (opt-forms
              (mapcar #'(lambda (opt-spec)
                          (multiple-value-bind (var val) (parse-optional-spec opt-spec)
                            `(defaultf ,var ,val)))
                      optionals))
             (key-forms
              (when keys?
  
negative.code:   (values (if (symbolp spec) spec (first spec))
            (when (listp spec) (second spec))))
  
  (defpsmacro defaultf (name value suppl)
    `(progn
       ,@(when suppl `((var ,suppl t)))
       (when (=== ,name undefined)
         (setf ,name ,value ,@(when suppl (list suppl nil))))))
  
  (defun parse-extended-function (lambda-list body &optional name)
    "Returns two values: the effective arguments and body for a function with
  