anchor.diff:  
   (defmacro define-unbound-variables (&rest variables)
     `(progn ,@(mapcar (fun `(defvar ,@(ensure-list _))) variables)))
  +
  +(defmacro define-print-object (((object class) &key (identity t) (type t)) &body body)
  +  (with-gensyms (stream)
  +    `(defmethod print-object ((,object ,class) ,stream)
  +      (print-unreadable-object (,object ,stream :type ,type :identity ,identity)
  +        (let ((*standard-output* ,stream)) ,@body)))))
  
positive.code: ;;;;
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  (in-package :sheeple)
  
  (declaim (inline error-when))
  (defun error-when (condition error-datum &rest error-args)
  
negative.code: 	((null (cdr args)) (car args))
  	(t `(aif ,(car args) (aand ,@(cdr args))))))
  
  (declaim (inline aconsf-helper))
  (defun aconsf-helper (alist key value)
    (acons key value alist))
  