anchor.diff:                 :documentation "List of everyone who lives in the town, marked by their clothing choice.")
      (styles :initarg :styles
              :accessor styles
  -           :documentation "Available styles. Styles are always represented by characters.")
  -   (hipsterish-tendency :initarg :hipsterish-tendency
  -                        :accessor hipsterish-tendency
  -                        :documentation "How likely would any individual be nonconformist at any given time."))
  +           :documentation "Available styles. Styles are always represented by characters."))
     (:documentation "A hipster town at a particular time."))
   
   (defclass delayed-town (town-snapshot)
  
positive.code:   (:method ((town town-snapshot))
      (make-instance
       'town-snapshot
       :hipsterish-tendency (hipsterish-tendency town)
       :styles              (copy-seq (styles town))
       :population          (map 'vector #'copy (population town))
       :time                (ticks town)))
    (:method ((town delayed-town))
      (make-instance
       'delayed-town
       :hipsterish-tendency (hipsterish-tendency town)
       :styles              (copy-seq (styles town))
       :population          (map 'vector #'copy (population town))
       :time                (ticks town)
  
negative.code:   (when (numberp styles)
      (setf styles (subseq *style-character-list* 0 styles)))
    (make-instance 'town-snapshot
                   :population (generate-random-town population styles volatile hipsterish-tendency)
                   :styles styles))
  
  (defun make-delayed-town (population period &key (hipsterish-tendency 2/3) (styles #(#\# #\.)) volatile)
    (when (numberp styles)
      (setf styles (subseq *style-character-list* 0 styles)))
    (make-instance 'delayed-town
                   :population (generate-random-town population styles volatile hipsterish-tendency)
                   :period period
                   :history (make-array (list period population) :adjustable volatile :initial-element nil)
                   :styles styles))
  
  (defmethod initialize-instance :after ((instance delayed-town) &key)
  