copy-whole-line2.el

(defun copy-whole-line2 (&optional arg)
  "Copy current line."
  (interactive "p")
  (or arg (setq arg 1))
  (if (and (> arg 0) (eobp) (save-excursion (forward-visible-line 0) (eobp)))
      (signal 'end-of-buffer nil))
  (if (and (< arg 0) (bobp) (save-excursion (end-of-visible-line) (bobp)))
      (signal 'beginning-of-buffer nil))
  (unless (eq last-command 'copy-region-as-kill)
    (kill-new "")
    (setq last-command 'copy-region-as-kill))
  (cond ((zerop arg)
         (save-excursion
           (copy-region-as-kill (progn (back-to-indentation) (point))
                                (progn (end-of-visible-line) (point)))))
        ((< arg 0)
         (save-excursion
           (copy-region-as-kill (progn (end-of-visible-line) (point))
                                (progn (forward-visible-line arg)
                                       (back-to-indentation) (point)))))
        ((or (> arg 1) (eq current-prefix-arg 1))
         (save-excursion
           (copy-region-as-kill (progn (back-to-indentation) (point))
                                (progn (forward-visible-line (1+ arg))
                                       (unless (bobp) (backward-char)) (point)))))
        (t
         (save-excursion
           (copy-region-as-kill (progn (back-to-indentation) (point))
                                (progn (forward-visible-line arg)
                                       (unless (bobp) (backward-char)) (point))))))
  (message "Copied from \"%s\"." (substring (car kill-ring-yank-pointer) 0 nil)))