backquote upon variable for :eval

backquote upon variable for :eval

[Heime]

I am using the backquote, but I get errors when using ,tknm

How can this be fixed ?  Perhaps I got to arrange the code in a different way ?


(defun vodil-ellipses (bfname wmax &optional actn)
  (if (equal actn 'concat)
      (concat (substring bfname 0 (- wmax 1)) "… ")
    (truncate-string-to-width bfname wmax nil nil "…")) )


(defun vodil-bfnap (wmax &optional actn)

  (setq-default mode-line-buffer-identification
    `(:eval
        (let* ( (bfnm (buffer-name (window-buffer)))
                (tknm (if (> (length bfnm) wmax)
                          (vodil-ellipses bfnm wmax actn)
                        bfnm)) )
          (propertized-buffer-identification (format " %s " ,tknm))))))

Re: backquote upon variable for :eval

[Manuel Giraud via Users list for the GNU Emacs text editor]

Heime <heimeborgia@protonmail.com> writes:

> I am using the backquote, but I get errors when using ,tknm
>
> How can this be fixed ?  Perhaps I got to arrange the code in a
> different way ?

Yes I think that you should re-arrange and re-read "(elisp) Backquote"
and maybe "(elisp) Evaluation" too.

[...]

> (defun vodil-bfnap (wmax &optional actn)
>
>   (setq-default mode-line-buffer-identification
>     `(:eval
>         (let* ( (bfnm (buffer-name (window-buffer)))
>                 (tknm (if (> (length bfnm) wmax)
>                           (vodil-ellipses bfnm wmax actn)
>                         bfnm)) )
>           (propertized-buffer-identification (format " %s " ,tknm))))))

What could contain an evaluation of tknm here?
-- 
Manuel Giraud

Re: backquote upon variable for :eval

[Heime]

Sent with Proton Mail secure email.

On Monday, July 29th, 2024 at 8:24 AM, Manuel Giraud via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org> wrote:

> Heime heimeborgia@protonmail.com writes:
> 
> > I am using the backquote, but I get errors when using ,tknm
> > 
> > How can this be fixed ? Perhaps I got to arrange the code in a
> > different way ?
> 
> 
> Yes I think that you should re-arrange and re-read "(elisp) Backquote"
> and maybe "(elisp) Evaluation" too.
> 
> [...]
> 
> > (defun vodil-bfnap (wmax &optional actn)
> > 
> > (setq-default mode-line-buffer-identification
> > `(:eval
> > (let* ( (bfnm (buffer-name (window-buffer)))
> > (tknm (if (> (length bfnm) wmax)
> > (vodil-ellipses bfnm wmax actn)
> > bfnm)) )
> > (propertized-buffer-identification (format " %s " ,tknm))))))
> 
> 
> What could contain an evaluation of tknm here?
> --
> Manuel Giraud

Have done this, but although it works, the buffer name is always *scratch*

(defun vodil-bfnap (wmax &optional actm)

  (let* ( (bfnm (buffer-name (window-buffer)))
          (tknm (if (> (length bfnm) wmax)
                    (vodil-ellipses bfnm wmax actm)
                  bfnm)))
    (setq-default mode-line-buffer-identification
      `(:eval  (propertized-buffer-identification (format " %s " ,tknm))))))

backquote upon variable for :eval

[Christopher Dimech]

> Sent: Monday, July 29, 2024 at 8:44 AM
> From: "Heime" <heimeborgia@protonmail.com>
> To: "Manuel Giraud" <manuel@ledu-giraud.fr>
> Cc: "Heime via Users list for the GNU Emacs text editor" <help-gnu-emacs@gnu.org>
> Subject: Re: backquote upon variable for :eval
>
>
>
>
>
>
> Sent with Proton Mail secure email.
>
> On Monday, July 29th, 2024 at 8:24 AM, Manuel Giraud via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org> wrote:
>
> > Heime heimeborgia@protonmail.com writes:
> >
> > > I am using the backquote, but I get errors when using ,tknm
> > >
> > > How can this be fixed ? Perhaps I got to arrange the code in a
> > > different way ?
> >
> >
> > Yes I think that you should re-arrange and re-read "(elisp) Backquote"
> > and maybe "(elisp) Evaluation" too.
> >
> > [...]
> >
> > > (defun vodil-bfnap (wmax &optional actn)
> > >
> > > (setq-default mode-line-buffer-identification
> > > `(:eval
> > > (let* ( (bfnm (buffer-name (window-buffer)))
> > > (tknm (if (> (length bfnm) wmax)
> > > (vodil-ellipses bfnm wmax actn)
> > > bfnm)) )
> > > (propertized-buffer-identification (format " %s " ,tknm))))))
> >
> >
> > What could contain an evaluation of tknm here?
> > --
> > Manuel Giraud
>
> Have done this, but although it works, the buffer name is always *scratch*
>
> (defun vodil-bfnap (wmax &optional actm)
>
>   (let* ( (bfnm (buffer-name (window-buffer)))
>           (tknm (if (> (length bfnm) wmax)
>                     (vodil-ellipses bfnm wmax actm)
>                   bfnm)))
>     (setq-default mode-line-buffer-identification
>       `(:eval  (propertized-buffer-identification (format " %s " ,tknm))))))


In your function, the values of wmax and actm need to be evaluated because they are
external variables passed as arguments.  The other variables (bfnm and tknm) are local
to the let* block and do not require special handling with the backquote-comma syntax
for evaluation.

(defun vodil-bfnap (wmax &optional actn)

  (setq-default mode-line-buffer-identification
    `(:eval
        (let* ( (bfnm (buffer-name (window-buffer)))
                (tknm (if (> (length bfnm) ,wmax)
                          (vodil-ellipses bfnm ,wmax ,actn)
                        bfnm)) )

          (propertized-buffer-identification (format " %s " tknm))))))