sum-column

gistfile1.sls

(defun sum-column ()
  "Sums a column of numbers starting at point"
  (interactive)
  (save-excursion
    (if (and (not (= (current-column) 0))
             (re-search-backward "[ \t]" 0 t ))
        (forward-char))
    (let ((retn 0)
          (old-column (current-column))
          (old-next-line-add-newlines))
      (setq next-line-add-newlines nil)
      (while (not
              (looking-at "^[ \t]*$"))
        (move-to-column old-column t)
        (if (and (looking-at "-?[0123456789]+")
                 (eq (current-column) old-column))
            (setq retn (+ retn (string-to-number (current-word)))))
        (next-line)
        (beginning-of-line))
      (next-line)
      (next-line)
      (move-end-of-line 0)
      (insert (make-string (- old-column (current-column)) 32))
      (insert (number-to-string retn))
      (setq next-line-add-newlines old-next-line-add-newlines)
      retn)))