Use of return in dolist

Use of return in dolist

[Heime via Users list for the GNU Emacs text editor]

I want to understand what return does?  I is supposed to exit the dolist.
But does return also return a value.  Does in also exit the function or not? 


(defun amazones-okul-kntlr (actm-seqr)
  "TODO"

  ;; Make ACTM-SEQR a list, even if a single symbol is passed.
  (let ( (actm-seqr
           (if (listp actm-seqr) actm-seqr (list actm-seqr))) )

    (dolist (actm actm-seqr)
      (pcase actm

  ;; PCASE
  ('armg
     (message "ARMG amazones-okul-kntlr")
     (add-to-list 'load-path (amazones-fpln-waypt "OKUL" 'sec))
     (require 'okul)
     (require 'prevodilac))

  ;; PCASE
  ('go
     (message "GO amazones-okul-kntlr")
     (okul-modeline "primitive"))

  ;; PCASE
  ('nogo
     (message "NOGO amazones-okul-kntlr")
     (return))

  ;; PCASE
  (_
     (message "NOGO amazones-okul-kntlr")
     (message " └── ACTM Unrecognised: %s" actm)
     (return)) ))) )

Re: Use of return in dolist

[Joel Reicher]

Heime via Users list for the GNU Emacs text editor 
<help-gnu-emacs@gnu.org> writes:

> I want to understand what return does?  I is supposed to exit 
> the dolist.  But does return also return a value.  Does in also 
> exit the function or not?

What does the documentation or definition for it say?

Regards,

        - Joel

Re: Use of return in dolist

[Heime via Users list for the GNU Emacs text editor]

Sent with Proton Mail secure email.

On Wednesday, January 1st, 2025 at 4:31 PM, Joel Reicher <joel.reicher@gmail.com> wrote:

> Heime via Users list for the GNU Emacs text editor
> help-gnu-emacs@gnu.org writes:
> 
> > I want to understand what return does? I is supposed to exit
> > the dolist. But does return also return a value. Does in also
> > exit the function or not?
> 
> 
> What does the documentation or definition for it say?
> 
> Regards,
> 
> - Joel

I cannot do C-h f return

Re: Use of return in dolist

[Joel Reicher]

Heime <heimeborgia@protonmail.com> writes:

> On Wednesday, January 1st, 2025 at 4:31 PM, Joel Reicher 
> <joel.reicher@gmail.com> wrote:
>
>> Heime via Users list for the GNU Emacs text editor 
>> help-gnu-emacs@gnu.org writes:
>>
>>> I want to understand what return does? I is supposed to exit 
>>> the dolist. But does return also return a value. Does in also 
>>> exit the function or not?
>>
>> What does the documentation or definition for it say?
>
> I cannot do C-h f return

That would suggest the function doesn't exist at all. Doesn't the 
code give an error? Is it your code, and if so why did you write 
"(return)"?

Regards,

        - Joel

Re: Use of return in dolist

[Eduardo Ochs]

On Wed, 1 Jan 2025 at 20:10, Heime via Users list for the GNU Emacs
text editor <help-gnu-emacs@gnu.org> wrote:
>
> I cannot do C-h f return

Try:

(defun eek (str) (execute-kbd-macro (read-kbd-macro str)))
(eek "M-x apropos RET return RET")
(eek "C-h f cl-return RET")

  Cheers,
    Eduardo

Re: Use of return in dolist

[Eduardo Ochs]

On Wed, 1 Jan 2025 at 21:42, Eduardo Ochs <eduardoochs@gmail.com> wrote:
>
> On Wed, 1 Jan 2025 at 20:10, Heime via Users list for the GNU Emacs
> text editor <help-gnu-emacs@gnu.org> wrote:
> >
> > I cannot do C-h f return
>
> Try:
>
> (defun eek (str) (execute-kbd-macro (read-kbd-macro str)))
> (eek "M-x apropos RET return RET")
> (eek "C-h f cl-return RET")
>
>   Cheers,
>     Eduardo

Try this too:

;; See: (info "(cl)Blocks and Exits")
(defun myinsert (o) (insert (format "\n%S" o)))
(dolist (i '(2 3 5)) (myinsert i))
(cl-block nil (dolist (i '(2 3 5 8)) (if (= i 5) (cl-return) (myinsert i))))

  Cheers,
    E.

Re: Use of return in dolist

[Jean Louis]

* Eduardo Ochs <eduardoochs@gmail.com> [2025-01-02 04:23]:
> Try this too:
> 
> ;; See: (info "(cl)Blocks and Exits")
> (defun myinsert (o) (insert (format "\n%S" o)))
> (dolist (i '(2 3 5)) (myinsert i))
2
3
5
> (cl-block nil (dolist (i '(2 3 5 8)) (if (= i 5) (cl-return) (myinsert i))))
2
3

I have tried the above by using M-e evaluation after M-x eev-beginner RET

I am fan of `while`:

;; this one
(let ((i '(2 3 5 8))
      (no-go t))
  (while no-go
    (let ((item (pop i)))
      (cond ((= item 5) (setq no-go nil))
	    (t (insert (format "\n%S" item)))))))
2
3

;; Or this one:
(let ((i '(2 3 5 8)))
  (while (and i (not (= (car i) 5)))
    (insert (format "\n%S" (car i)))
    (setq i (cdr i))))
2
3

-- 
Jean Louis