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From: Jean Louis <bugs@gnu.support>
To: Hongyi Zhao <hongyi.zhao@gmail.com>
Cc: help-gnu-emacs <help-gnu-emacs@gnu.org>
Subject: Re: append, push, and add-to-list.
Date: Sun, 4 Jul 2021 07:35:44 +0300	[thread overview]
Message-ID: <YOE6oKkgtmA5imCI@protected.localdomain> (raw)
In-Reply-To: <CAGP6PO+0+wYDe6aeS2w5WXusJvMapVzoThJSnYhpfaYaGNCnbw@mail.gmail.com>

* Hongyi Zhao <hongyi.zhao@gmail.com> [2021-07-04 06:19]:
> I've noticed there are some similar functions, i.e., append, push, and
> add-to-list, for revising/updating the content of a list. But I'm
> still not so clear on the specific use scenarios for them. Consider
> the following command [1]:
> 
> (push '(company-capf company-ispell) company-backends)
> 
> What's the equivalent representations using append and add-to-list?
> Which methods are preferable?

It is recommended to review documentation for each function by using
{C-h f} -

- function add-to-list is traditionally rather used in configurations,
  how I see it, like (add-to-list 'load-path "/my/directory") or
  similar, instead, in programming code one shall rather use `push' or
  `cl-pushnew' as `add-to-list' adds only new unique elements;

Because you use it more for configurations, then add-to-list would be:

(add-to-list 'company-backends '(company-capf company-ispell))

and with append

(append company-backends '(company-capf company-ispell))



-- 
Jean

Take action in Free Software Foundation campaigns:
https://www.fsf.org/campaigns

In support of Richard M. Stallman
https://stallmansupport.org/



  reply	other threads:[~2021-07-04  4:35 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-04  3:18 append, push, and add-to-list Hongyi Zhao
2021-07-04  4:35 ` Jean Louis [this message]
2021-07-04  5:11   ` Hongyi Zhao
2021-07-04 11:28     ` Jean Louis
2021-07-04 13:50       ` Hongyi Zhao
2021-07-04 15:58         ` Jean Louis
2021-07-05  2:04           ` Hongyi Zhao
2021-07-04 16:01         ` [External] : " Drew Adams
2021-07-04 16:20     ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-04 16:19 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05  2:16   ` Hongyi Zhao
2021-07-05  3:48     ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05  4:31       ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05  5:07         ` Hongyi Zhao
2021-07-05  5:50           ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05  6:19             ` Hongyi Zhao
2021-07-05  5:06     ` Jean Louis
2021-07-05  6:22       ` Hongyi Zhao
2021-07-05  6:32         ` Emanuel Berg via Users list for the GNU Emacs text editor
  -- strict thread matches above, loose matches on Subject: below --
2021-07-05 14:37 Drew Adams
2021-07-05 14:53 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05 15:19   ` Stefan Monnier via Users list for the GNU Emacs text editor
2021-07-05 16:46     ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-06 19:54       ` Jean Louis
2021-07-06 20:08         ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05 15:41   ` tomas
2021-07-05 16:58     ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05 17:21       ` tomas
2021-07-06  1:17         ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05 18:10       ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05 18:18         ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05 18:11       ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05 18:39         ` Stefan Monnier via Users list for the GNU Emacs text editor
2021-07-05 20:35           ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-06 19:57         ` Jean Louis
2021-07-06 20:16           ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-06 19:56       ` Jean Louis
2021-07-06 20:15         ` Emanuel Berg via Users list for the GNU Emacs text editor

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