anchor.diff:                   (preprocessed-suggestions (mapcar #'copy-object
                                                      (initial-suggestions source))))
                (setf preprocessed-suggestions
  -                   (maybe-funcall (filter-preprocessor source)
  -                                  preprocessed-suggestions source input))
  +                   (if (filter-preprocessor source)
  +                       (maybe-funcall (filter-preprocessor source)
  +                                      preprocessed-suggestions source input)
  +                       (list (make-instance 'suggestion
  +                                            :value input
  +                                            :properties (maybe-funcall (suggestion-property-function source)
  +                                                                       input)
  +                                            :match-data ""))))
                ;; TODO: Should we really reset the suggestions here?
                (setf (slot-value source 'suggestions) '())
                (if (or (str:empty? input)
  
positive.code: 
       (initial-suggestions '()
                            :reader initial-suggestions
                            :documentation
                            "Suggestions used on initialization, before any
  user input is processed.
  
negative.code: display and match against, see `active-properties'.")
  
       (filter #'fuzzy-match
               :type (or null function)
               :documentation
               "Takes `input' and a `suggestion' and return a new suggestion, or
  nil if the suggestion is discarded.")
  