anchor.diff:    (:method ((town town-snapshot) &key (stream t) limit specific-style)
       (with-accessors ((age ticks) (members population)) town
         (if specific-style
  -          (format stream "~&~3d: ~{~a~}~:[~;…~]" age (mapcar #'(lambda (a) (if (char-equal specific-style a)
  -                                                                                         specific-style
  -                                                                                         #\Space))
  -                                                                       (subseq members 0 limit)) limit)
  -          (format stream "~&~3d: ~{~a~}~:[~;…~]" age (subseq members 0 limit) limit)))))
  +          (format stream "~&~3d: ~{~a~}~:[~;…~]" age (substitute-if #\Space #'(lambda (a) (char-not-equal specific-style a))
  +                                                                    (mapcar #'styles (subseq members 0 limit))) limit)
  +          (format stream "~&~3d: ~{~a~}~:[~;…~]" age (mapcar #'styles (subseq members 0 limit)) limit)))))
   
   (defgeneric print-popularity (town &key stream limit)
     (:documentation "Prints out the styles and its percentage popularity, along with a genreation number, truncated to [limit] styles if provided.")
  
positive.code:       (format stream "~&~3d:  " age)
        (loop for i across styles
              for j from 0 below (or limit (length styles))
              do (format stream "~20@<~a ~7,2f%~>" i (/ (count-if #'(lambda (a) (char-equal i a)) members)
                                                   (length members)
                                                   1/100))))))
  
  
negative.code: ;;; Classes
  
  (defstruct inhabitant
    (type :hipster)
    (style #\.)
    hipsterish-tendency)
  
  (defclass town-snapshot ()
    ((ticks :initform 0
  