anchor.diff:           (p 0)
            (pj 0))
       (declare (type array-index d m p pj))
  +    (when (minusp d)
  +      (setf d 0))
       (dotimes (i x-len)
         (declare (type array-index i))
         (let ((ch (char x i)))
  
positive.code:   "Returns normalized Levenshtein distance between X and Y. Result is a real
  number from 0 to 1, where 0 signifies no similarity between the strings,
  while 1 means exact match."
    (- 1 (/ (levenshtein x y)
            (max (length x)
                 (length y)))))
  
  (defun norm-damerau-levenshtein (x y)
    "Returns normalized Damerau-Levenshtein distance between X and Y. Result
  is a real number from 0 to 1, where 0 signifies no similarity between the
  strings, while 1 means exact match."
    (- 1 (/ (damerau-levenshtein x y)
            (max (length x)
                 (length y)))))
  
  (defun fast-find (char str str-len &optional (start 0))
    "Checks if CHAR is in STR. This function is supposed to be inlined."
  
negative.code:              done)
              ((or (null j) done))
            (declare (type (or array-index null) j))
            (when (and j (<= (the array-index (abs (- i j)))
                             d))
              (when (and (plusp pj)
                         (< j pj))
                (incf p))
  