anchor.diff:       summing 1))
   
   (defun hash-list-keys (hash-list)
  -  "This function returns a list of the keys that are present in every element of the list"
  +  "This function returns a list of the keys that are present in every element of the list."
     (loop with counts = (make-hash-table :test 'equal)
        for hash in hash-list
        do (loop for key being the hash-keys in hash
  
positive.code: 
  (defun hash-list-remove-columns (hash-list &rest columns)
    (loop for hash in hash-list
       do (loop for column in columns
             do (remhash column hash))))
  
  (defun hash-list-first-index-of (hash-list &rest key-value-pairs)
    (loop for row in hash-list
  
negative.code:                     (alist-to-plist value)
                      value))))
  
  (defun parse-if-number (value)
    (if (scan "^(?=.)([+-]?([0-9]*)(\.([0-9]+))?)$" value)
        (parse-number value)
        value))
  
  (defun hash-list-from-csv (filename &key headers-in-file header-list
                                        (clean-headers t)
                                        (parse-numbers t))
    (let* ((rows (cl-csv:read-csv
                  (if (pathnamep filename) filename (pathname filename))))
           (fields (cond
  