A small Common Lisp program to sum up file sizes from `ls -l`.

shlyfile.lisp

;; https://twitter.com/potix2/status/371962749246394368

;; Usage
;;   $ ls -l | shly sumsize

(ql:quickload :cl-ppcre)
(defun sumsize ()
  (loop with sum = 0 
        for line = (read-line *standard-input* nil)
        while line
        for size = (nth 3 (ppcre:split "\\s+" line))
        when (stringp size)
          do (incf sum (parse-integer size))
        finally (return sum)))