anchor.diff:    (make-presentation-type-specifier `(completion ,elements)
                                       :name-key name-key
                                       :documentation-key documentation-key
  -                                    :partial-completers partial-completers)
  +                                    :partial-completers partial-completers
  +                                    :printer printer
  +                                    :highlighter highlighter)
     :options #.+completion-options+)
   
   (define-presentation-type-abbreviation member-sequence (sequence
  
positive.code:    `(completion ,sequence ,@(and testp `(:test ,test)))
     :name-key name-key
     :documentation-key documentation-key
     :partial-completers partial-completers)
    :options #.+completion-options+)
  
  (defun member-alist-value-key (element)
  
negative.code:             documentation-key
              (partial-completers '(#\Space))
              (separator #\,)
              (echo-space t)
              (printer #'write-token)
              (highlighter #'highlight-completion-choice))
    :inherit-from t)
  
  (define-presentation-method presentation-typep (object
  