anchor.diff:  
   (defvar *style-character-list* "#.=?O|+*_:~X;'$%^\"/vq`"
     "List of characters eligible for styles. This can be rebound if you desire more characters.")
  +
  +(defvar *simulation-parameters*
  +  '((:stickiness-in-wandering . 5/6)
  +    (:stickiness-in-deconforming . 10/11)))
   
   ;;; Classes
   
  
positive.code: (defgeneric tick! (town)
    (:documentation "Destructively modifies a snapshot to become the next iteration of the simulation.")
    (:method ((town town-snapshot))
      (deconform town 10/11))
    (:method ((town delayed-town))
      (if (null (aref (town-history town) (mod (1+ (ticks town)) (period town)) 0))
          (wander town 5/6)        ; While the history fills up, randomly wander, changing fashions 1/6 of the time
          (deconform town 10/11))) ; After that, proceed as normal
    (:method :after ((town town-snapshot))
      (incf (ticks town)))
    (:method :after ((town delayed-town))
  
negative.code: ;;; Other methods
  
  (defgeneric nth-inhabitant (town n)
    (:documentation "Finds the nth (zero-based) inhabitant in a town.")
    (:method ((town town-snapshot) (n number))
       (aref (population town) n)))
  
  