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Re: append, push, and add-to-list.


From: Jean Louis
Subject: Re: append, push, and add-to-list.
Date: Sun, 4 Jul 2021 07:35:44 +0300
User-agent: Mutt/2.0.7+183 (3d24855) (2021-05-28)

* 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

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