anchor.diff:  						  extends/including
   						  extends/excluding)
     (flet ((ensure-package (p)
  -	   (let ((package (etypecase p
  -			    (package p)
  -			    ((or symbol string) (find-package p)))))
  -	     (unless package
  +	   (or (find-package p)
   	       ;; might want to be able to continue
  -	       (error "No package named ~S" p))
  -	     package))
  +	       (error "No package named ~S" p)))
   	 (ensure-external-symbol (d p)
   	   (multiple-value-bind (s state)
   	       (find-symbol (etypecase d
  
positive.code:      (let ((found (find-package package/name)))
         (values (intern (if found
  			   (package-name found)
  			   (typecase package/name
  			     (string package/name)
  			     (symbol (symbol-name package/name))))
  		       (find-package :keyword))
  
negative.code: ;;;
  
  (defun clone-packages-to-package (froms to)
    (let ((to (or (find-package to)
                  (make-package to :use '()))))
      (loop :for f :in froms
            :for from := (find-package f)
            :for used := (package-use-list from)
            :for shadows := (package-shadowing-symbols from)
            :for exports := (let ((exps '()))
  