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From: Marco Wahl <marcowahlsoft@gmail.com>
To: help-gnu-emacs@gnu.org
Subject: Re: Understanding dotimes skipping by 2
Date: Fri, 28 Sep 2018 01:14:59 +0200	[thread overview]
Message-ID: <84a7o28rd8.fsf@gmail.com> (raw)
In-Reply-To: mailman.1418.1538089091.1284.help-gnu-emacs@gnu.org

Tim Johnson <tim@akwebsoft.com> writes:

> the following code snippet is as follows:
> (setq l `(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

Looks like "/" is a variable which gets bound to the values of 0 up to
(length l) and the result of the loop is 2.

It's in the documentation (C-h f dotimes).


HTH
-- 
Marco


       reply	other threads:[~2018-09-27 23:14 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <mailman.1418.1538089091.1284.help-gnu-emacs@gnu.org>
2018-09-27 23:14 ` Marco Wahl [this message]
2018-09-27 23:17   ` Understanding dotimes skipping by 2 Eric Abrahamsen
2018-09-27 23:59     ` Tim Johnson
2018-09-27 23:32   ` Tim Johnson
2018-09-27 22:48 Tim Johnson
2018-09-28  1:29 ` 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

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