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

[Jean Louis]

* Hongyi Zhao <hongyi.zhao@gmail.com> [2021-07-05 05:17]:
> On Mon, Jul 5, 2021 at 12:19 AM Emanuel Berg via Users list for the
> GNU Emacs text editor <help-gnu-emacs@gnu.org> wrote:
> >
> > Hongyi Zhao wrote:
> >
> > > 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]
> >
> > `nconc', `cl-pushnew', (setq lst `(,@lst el)) ...
> 
> Does the following append `el' to `lst'?
> 

(defvar lst '()) ⇒ lst

(setq lst `(,@lst el)) ⇒ (el)

lst  ⇒ (el)

I see it does when variable `list' is defined in advance.

-- 
Jean

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