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From: Tim Johnson <tim@akwebsoft.com>
To: Emacs <Help-gnu-emacs@gnu.org>
Subject: Understanding dotimes skipping by 2
Date: Thu, 27 Sep 2018 14:48:40 -0800	[thread overview]
Message-ID: <20180927224840.GA2161@mail.akwebsoft.com> (raw)

using GNU Emacs 26.1 (GTK+ Version) on ubuntu 14.04
 
the following code snippet is as follows:
(setq l `(1 2 3 4 5 6 7 8 9 0))
(1 2 3 4 5 6 7 8 9 0)
;; iterate through a list two elements at a time
(let ((x 0))
  (dotimes (/ (length l) 2)
    (progn
      (insert (format "%s %s, " (nth x l) (nth (+ x 1) l)))
      (setq x (+ x 2)))))

;; and below are the results
1 2, 3 4, 5 6, 7 8, 9 0, nil nil, nil nil, nil nil, nil nil, nil nil, 2

I'm confused about the output (nil etc...)which follow the expected numbers. 
could someone explain?
P.S. I get the same output without the `progn form
thanks
-- 
Tim Johnson
http://www.tj49.com



             reply	other threads:[~2018-09-27 22:48 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-27 22:48 Tim Johnson [this message]
2018-09-28  1:29 ` Understanding dotimes skipping by 2 Van L
2018-09-28  2:56   ` Tim Johnson
2018-09-28  9:11   ` Joost Kremers
2018-09-28  9:50     ` Van L
2018-09-28 12:23       ` Eli Zaretskii
2018-09-28 12:26         ` Van L
2018-09-28 17:47     ` Tim Johnson
2018-09-28 18:16     ` Noam Postavsky
     [not found] <mailman.1418.1538089091.1284.help-gnu-emacs@gnu.org>
2018-09-27 23:14 ` Marco Wahl
2018-09-27 23:17   ` Eric Abrahamsen
2018-09-27 23:59     ` Tim Johnson
2018-09-27 23:32   ` Tim Johnson

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