anchor.diff:  (defpackage cl-commons
     (:use :cl)
     (:export :split-string-in-chars
  +           :string-append
              :average
              :median
              :compose
  
positive.code: (defun split-string-in-chars (string)
    "Splits a string in it's charachters."
    (map 'list #'identity string))
  
  (defun average (elements)
    (/ (apply #'+ elements) (length elements)))
  
negative.code: 
  (defun partial-right (fn &rest partial-args)
    (apply #'partial (flip fn) partial-args))
  
  