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From: steve-humphreys@gmx.com
To: steve-humphreys@gmx.com
Cc: Help Gnu Emacs <help-gnu-emacs@gnu.org>
Subject: Re: Understanding the "let" construct and the setting of variables
Date: Thu, 17 Dec 2020 01:25:11 +0100	[thread overview]
Message-ID: <trinity-2c32a017-c34b-4378-88c7-23916337ac3f-1608164711813@3c-app-mailcom-bs11> (raw)
In-Reply-To: <trinity-5874c8ab-7034-425f-8175-8c77def9363b-1608163806460@3c-app-mailcom-bs11>

Let's introspect two questions.

1. In what simple circumstances would one use a "setq" in the body of a let?
2. What simple option does one have that is more advantageous than using a "setq"?



> Sent: Thursday, December 17, 2020 at 1:10 AM
> From: steve-humphreys@gmx.com
> To: "Help Gnu Emacs" <help-gnu-emacs@gnu.org>
> Subject: Understanding the "let" construct and the setting of variables
>
> I have been writing some elisp to set the time grid in the agenda.
> The discussion progressed towards the use of the "let" construct.
>
> But, the discussion got too advanced for me to follow the different
> points of view and make a decision.
>
> This message is for showing some examples, of how to set and use variables
> in a "let", because people criticise using "setq".  But discussion needs
> simple examples  that would not overwhelm a relative beginner.
>
> (defun timfutur ()
>    (interactive)
>    (setq tim 845)
>    (setq tsk 80)
>
>    (setq thr (/ tim 100))
>    (setq tmn (- tim (* thr 100)))
>
>    (setq tinc_mn (+ tmn tsk))
>    (setq tinc_hr (/ (+ tmn tsk) 60))
>    (setq tinc_mn (- tinc_mn (* tinc_hr 60)) )
>
>    (setq thr_futur (* (+ thr tinc_hr) 100)  )
>    (setq tmn_futur tinc_mn)
>    (setq tim_out (+ thr_futur tmn_futur))
>
>
>
>
>
>



  parent reply	other threads:[~2020-12-17  0:25 UTC|newest]

Thread overview: 50+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-17  0:10 Understanding the "let" construct and the setting of variables steve-humphreys
2020-12-17  0:21 ` Joost Kremers
2020-12-17  2:08   ` steve-humphreys
2020-12-17  3:12     ` steve-humphreys
2020-12-17  8:01       ` Joost Kremers
2020-12-17  8:31         ` steve-humphreys
2020-12-17  8:50           ` Joost Kremers
2020-12-17  8:10     ` Joost Kremers
2020-12-17  8:43       ` steve-humphreys
2020-12-17  8:56         ` Joost Kremers
2020-12-18 20:48           ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-18 20:46         ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-18 21:07           ` Jean Louis
2020-12-18 22:31           ` tomas
2020-12-18 20:39       ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-17  2:49   ` steve-humphreys
2020-12-17  7:58     ` Joost Kremers
2020-12-17 16:55       ` Drew Adams
2020-12-17 20:11         ` steve-humphreys
2020-12-17 21:57           ` Drew Adams
2020-12-17 22:35           ` Michael Heerdegen
2020-12-18  9:01             ` tomas
2020-12-18  9:16               ` Michael Heerdegen
2020-12-18 20:55                 ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-19  2:17                   ` Michael Heerdegen
2020-12-19  2:52                     ` Drew Adams
2020-12-19  5:15                     ` Stefan Monnier
2020-12-18 20:33   ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-17  0:25 ` steve-humphreys [this message]
2020-12-17  0:35   ` steve-humphreys
2020-12-17  1:05     ` Joost Kremers
2020-12-17  1:20       ` steve-humphreys
2020-12-18 20:58         ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-17  4:34   ` Jean Louis
2020-12-17  5:12     ` steve-humphreys
2020-12-19  6:06       ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-17  7:31     ` steve-humphreys
2020-12-19  5:55     ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-19  6:49       ` Jean Louis
2020-12-20  5:19         ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-18 17:14   ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-18 17:48     ` tomas
2020-12-18 15:33 ` Emanuel Berg via Users list for the GNU Emacs text editor
2020-12-18 18:12   ` Jean Louis
2020-12-18 18:20     ` Drew Adams
2020-12-18 18:45       ` Jean Louis
2020-12-18 19:16         ` Drew Adams
2020-12-18 20:00           ` Jean Louis
2020-12-18 21:27     ` Christopher Dimech
2020-12-19  6:23     ` Emanuel Berg via Users list for the GNU Emacs text editor

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