Printing comment-start of various modes

Printing comment-start of various modes

[Heime]

This function should print the value of comment-start for various modes,
but I am not getting any comment-start outputs from it.

(defun costart ()
  "Loop through various major modes and print the value of `comment-start`."

  (interactive)

  (let ( (modes '(sh-mode perl-mode python-mode
		 emacs-lisp-mode lisp-interaction-mode
                 org-mode tex-mode latex-mode texi-mode
                 c-mode c++-mode f90-mode fortran-mode
                 html-mode css-mode js-mode
                 java-mode php-mode) )

         (output-buffer (generate-new-buffer "Costart")) )

    (with-current-buffer output-buffer
      (insert "Mode \t\t Comment Start \n")
      (insert "---- \t\t ------------- \n"))

    (dolist (mode modes)
      (with-temp-buffer
        (funcall mode)
        (let ((comment-start (or comment-start "None")))
          (with-current-buffer output-buffer
            (insert (format "%s \t\t %s \n" mode comment-start))))))

    (switch-to-buffer output-buffer)))

Re: Printing comment-start of various modes

[Stephen Berman]

On Tue, 13 Aug 2024 20:09:57 +0000 Heime <heimeborgia@protonmail.com> wrote:

> This function should print the value of comment-start for various modes,
> but I am not getting any comment-start outputs from it.
>
> (defun costart ()
>   "Loop through various major modes and print the value of `comment-start`."
>
>   (interactive)
>
>   (let ( (modes '(sh-mode perl-mode python-mode
> 		 emacs-lisp-mode lisp-interaction-mode
>                  org-mode tex-mode latex-mode texi-mode
>                  c-mode c++-mode f90-mode fortran-mode
>                  html-mode css-mode js-mode
>                  java-mode php-mode) )
>
>          (output-buffer (generate-new-buffer "Costart")) )
>
>     (with-current-buffer output-buffer
>       (insert "Mode \t\t Comment Start \n")
>       (insert "---- \t\t ------------- \n"))
>
>     (dolist (mode modes)
>       (with-temp-buffer
>         (funcall mode)
>         (let ((comment-start (or comment-start "None")))
>           (with-current-buffer output-buffer
>             (insert (format "%s \t\t %s \n" mode comment-start))))))
>
>     (switch-to-buffer output-buffer)))

You successively bind mode-specific value of comment-start in a
temporary buffer, and then switch to output-buffer to print the values,
but this buffer is in fundamental-mode, where comment-start has the
value nil by default.  Using the temporary buffer seems superfluous, you
could just use output-buffer:

(defun costart ()
  "Loop through various major modes and print the value of `comment-start`."
  (interactive)
  (let ((modes '(sh-mode perl-mode python-mode
			 emacs-lisp-mode lisp-interaction-mode
			 org-mode tex-mode latex-mode texi-mode
			 c-mode c++-mode f90-mode fortran-mode
			 html-mode css-mode js-mode
			 java-mode php-mode) )
        (output-buffer (generate-new-buffer "Costart")))
    (with-current-buffer output-buffer
      (insert "Mode \t\t Comment Start \n")
      (insert "---- \t\t ------------- \n"))
    (dolist (mode modes)
      (with-current-buffer output-buffer
        (funcall mode)
        (let ((comment-start (or comment-start "None")))
          (insert (format "%s \t\t %s \n" mode comment-start)))))
    (switch-to-buffer output-buffer)
    (fundamental-mode)))

Steve Berman

Re: Printing comment-start of various modes

[Heime]

Sent with Proton Mail secure email.

On Wednesday, August 14th, 2024 at 9:13 AM, Stephen Berman <stephen.berman@gmx.net> wrote:

> On Tue, 13 Aug 2024 20:09:57 +0000 Heime heimeborgia@protonmail.com wrote:
> 
> > This function should print the value of comment-start for various modes,
> > but I am not getting any comment-start outputs from it.
> > 
> > (defun costart ()
> > "Loop through various major modes and print the value of `comment-start`."
> > 
> > (interactive)
> > 
> > (let ( (modes '(sh-mode perl-mode python-mode
> > emacs-lisp-mode lisp-interaction-mode
> > org-mode tex-mode latex-mode texi-mode
> > c-mode c++-mode f90-mode fortran-mode
> > html-mode css-mode js-mode
> > java-mode php-mode) )
> > 
> > (output-buffer (generate-new-buffer "Costart")) )
> > 
> > (with-current-buffer output-buffer
> > (insert "Mode \t\t Comment Start \n")
> > (insert "---- \t\t ------------- \n"))
> > 
> > (dolist (mode modes)
> > (with-temp-buffer
> > (funcall mode)
> > (let ((comment-start (or comment-start "None")))
> > (with-current-buffer output-buffer
> > (insert (format "%s \t\t %s \n" mode comment-start))))))
> > 
> > (switch-to-buffer output-buffer)))
> 
> 
> You successively bind mode-specific value of comment-start in a
> temporary buffer, and then switch to output-buffer to print the values,
> but this buffer is in fundamental-mode, where comment-start has the
> value nil by default. Using the temporary buffer seems superfluous, you
> could just use output-buffer:
> 
> (defun costart ()
> "Loop through various major modes and print the value of `comment-start`."
> (interactive)
> (let ((modes '(sh-mode perl-mode python-mode
> emacs-lisp-mode lisp-interaction-mode
> org-mode tex-mode latex-mode texi-mode
> c-mode c++-mode f90-mode fortran-mode
> html-mode css-mode js-mode
> java-mode php-mode) )
> (output-buffer (generate-new-buffer "Costart")))
> (with-current-buffer output-buffer
> (insert "Mode \t\t Comment Start \n")
> (insert "---- \t\t ------------- \n"))
> (dolist (mode modes)
> (with-current-buffer output-buffer
> (funcall mode)
> (let ((comment-start (or comment-start "None")))
> (insert (format "%s \t\t %s \n" mode comment-start)))))
> (switch-to-buffer output-buffer)
> (fundamental-mode)))
> 
> Steve Berman

What does it matter if the buffer is in fundamental-mode, when I am changing
the major mode ?  I still do not get the dolist insert for each mode.

Re: Printing comment-start of various modes

[Stephen Berman]

On Tue, 13 Aug 2024 21:32:50 +0000 Heime <heimeborgia@protonmail.com> wrote:

> Sent with Proton Mail secure email.
>
> On Wednesday, August 14th, 2024 at 9:13 AM, Stephen Berman
> <stephen.berman@gmx.net> wrote:
>
>> On Tue, 13 Aug 2024 20:09:57 +0000 Heime heimeborgia@protonmail.com wrote:
>>
>> > This function should print the value of comment-start for various modes,
>> > but I am not getting any comment-start outputs from it.
>> >
>> > (defun costart ()
>> > "Loop through various major modes and print the value of `comment-start`."
>> >
>> > (interactive)
>> >
>> > (let ( (modes '(sh-mode perl-mode python-mode
>> > emacs-lisp-mode lisp-interaction-mode
>> > org-mode tex-mode latex-mode texi-mode
>> > c-mode c++-mode f90-mode fortran-mode
>> > html-mode css-mode js-mode
>> > java-mode php-mode) )
>> >
>> > (output-buffer (generate-new-buffer "Costart")) )
>> >
>> > (with-current-buffer output-buffer
>> > (insert "Mode \t\t Comment Start \n")
>> > (insert "---- \t\t ------------- \n"))
>> >
>> > (dolist (mode modes)
>> > (with-temp-buffer
>> > (funcall mode)
>> > (let ((comment-start (or comment-start "None")))
>> > (with-current-buffer output-buffer
>> > (insert (format "%s \t\t %s \n" mode comment-start))))))
>> >
>> > (switch-to-buffer output-buffer)))
>>
>>
>> You successively bind mode-specific value of comment-start in a
>> temporary buffer, and then switch to output-buffer to print the values,
>> but this buffer is in fundamental-mode, where comment-start has the
>> value nil by default. Using the temporary buffer seems superfluous, you
>> could just use output-buffer:
>>
>> (defun costart ()
>> "Loop through various major modes and print the value of `comment-start`."
>> (interactive)
>> (let ((modes '(sh-mode perl-mode python-mode
>> emacs-lisp-mode lisp-interaction-mode
>> org-mode tex-mode latex-mode texi-mode
>> c-mode c++-mode f90-mode fortran-mode
>> html-mode css-mode js-mode
>> java-mode php-mode) )
>> (output-buffer (generate-new-buffer "Costart")))
>> (with-current-buffer output-buffer
>> (insert "Mode \t\t Comment Start \n")
>> (insert "---- \t\t ------------- \n"))
>> (dolist (mode modes)
>> (with-current-buffer output-buffer
>> (funcall mode)
>> (let ((comment-start (or comment-start "None")))
>> (insert (format "%s \t\t %s \n" mode comment-start)))))
>> (switch-to-buffer output-buffer)
>> (fundamental-mode)))
>>
>> Steve Berman
>
> What does it matter if the buffer is in fundamental-mode, when I am changing
> the major mode ?  I still do not get the dolist insert for each mode.

With the code I posted, I get this output (I evaluated and executed the
code after commenting out texi-mode and php-mode, because they were not
loaded in my running Emacs):

Mode 		 Comment Start
---- 		 -------------
sh-mode 		 #
perl-mode 		 #
python-mode 		 #
emacs-lisp-mode 		 ;
lisp-interaction-mode 		 ;
org-mode 		 #
tex-mode 		 %
latex-mode 		 %
c-mode 		 /*
c++-mode 		 //
f90-mode 		 !
fortran-mode 		 C
html-mode 		 <!--
css-mode 		 /*
js-mode 		 //
java-mode 		 //

If you don't get this output, I guess you didn't use the code I posted,
or something in your running Emacs changed how it works.  As for
changing output-buffer to fundamental-mode at the end, that's just to
restore its initial major-mode, otherwise it would have the major-mode
of the last major mode function evaluated (here, java-mode).

Instead of using comment-start as the let-bound variable, which in your
original code gets overriden by the value of the dynamically scoped
variable comment-start in output-buffer, you could use a variable name
that doesn't get shadowed, e.g. `cmnt-strt', for the let-bound variable.
Then you can keep the use of both the temporary buffer and
output-buffer.

Steve Berman

Re: Printing comment-start of various modes

[Heime]

Sent with Proton Mail secure email.

On Wednesday, August 14th, 2024 at 9:55 AM, Stephen Berman <stephen.berman@gmx.net> wrote:

> On Tue, 13 Aug 2024 21:32:50 +0000 Heime heimeborgia@protonmail.com wrote:
> 
> > Sent with Proton Mail secure email.
> > 
> > On Wednesday, August 14th, 2024 at 9:13 AM, Stephen Berman
> > stephen.berman@gmx.net wrote:
> > 
> > > On Tue, 13 Aug 2024 20:09:57 +0000 Heime heimeborgia@protonmail.com wrote:
> > > 
> > > > This function should print the value of comment-start for various modes,
> > > > but I am not getting any comment-start outputs from it.
> > > > 
> > > > (defun costart ()
> > > > "Loop through various major modes and print the value of `comment-start`."
> > > > 
> > > > (interactive)
> > > > 
> > > > (let ( (modes '(sh-mode perl-mode python-mode
> > > > emacs-lisp-mode lisp-interaction-mode
> > > > org-mode tex-mode latex-mode texi-mode
> > > > c-mode c++-mode f90-mode fortran-mode
> > > > html-mode css-mode js-mode
> > > > java-mode php-mode) )
> > > > 
> > > > (output-buffer (generate-new-buffer "Costart")) )
> > > > 
> > > > (with-current-buffer output-buffer
> > > > (insert "Mode \t\t Comment Start \n")
> > > > (insert "---- \t\t ------------- \n"))
> > > > 
> > > > (dolist (mode modes)
> > > > (with-temp-buffer
> > > > (funcall mode)
> > > > (let ((comment-start (or comment-start "None")))
> > > > (with-current-buffer output-buffer
> > > > (insert (format "%s \t\t %s \n" mode comment-start))))))
> > > > 
> > > > (switch-to-buffer output-buffer)))
> > > 
> > > You successively bind mode-specific value of comment-start in a
> > > temporary buffer, and then switch to output-buffer to print the values,
> > > but this buffer is in fundamental-mode, where comment-start has the
> > > value nil by default. Using the temporary buffer seems superfluous, you
> > > could just use output-buffer:
> > > 
> > > (defun costart ()
> > > "Loop through various major modes and print the value of `comment-start`."
> > > (interactive)
> > > (let ((modes '(sh-mode perl-mode python-mode
> > > emacs-lisp-mode lisp-interaction-mode
> > > org-mode tex-mode latex-mode texi-mode
> > > c-mode c++-mode f90-mode fortran-mode
> > > html-mode css-mode js-mode
> > > java-mode php-mode) )
> > > (output-buffer (generate-new-buffer "Costart")))
> > > (with-current-buffer output-buffer
> > > (insert "Mode \t\t Comment Start \n")
> > > (insert "---- \t\t ------------- \n"))
> > > (dolist (mode modes)
> > > (with-current-buffer output-buffer
> > > (funcall mode)
> > > (let ((comment-start (or comment-start "None")))
> > > (insert (format "%s \t\t %s \n" mode comment-start)))))
> > > (switch-to-buffer output-buffer)
> > > (fundamental-mode)))
> > > 
> > > Steve Berman
> > 
> > What does it matter if the buffer is in fundamental-mode, when I am changing
> > the major mode ? I still do not get the dolist insert for each mode.
> 
> 
> With the code I posted, I get this output (I evaluated and executed the
> code after commenting out texi-mode and php-mode, because they were not
> loaded in my running Emacs):
> 
> Mode Comment Start
> ---- -------------
> sh-mode #
> perl-mode #
> python-mode #
> emacs-lisp-mode ;
> lisp-interaction-mode ;
> org-mode #
> tex-mode %
> latex-mode %
> c-mode /*
> c++-mode //
> f90-mode !
> fortran-mode C
> html-mode <!--
> css-mode /*
> js-mode //
> java-mode //
> 
> If you don't get this output, I guess you didn't use the code I posted,
> or something in your running Emacs changed how it works. As for
> changing output-buffer to fundamental-mode at the end, that's just to
> restore its initial major-mode, otherwise it would have the major-mode
> of the last major mode function evaluated (here, java-mode).
> 
> Instead of using comment-start as the let-bound variable, which in your
> original code gets overriden by the value of the dynamically scoped
> variable comment-start in output-buffer, you could use a variable name
> that doesn't get shadowed, e.g. `cmnt-strt', for the let-bound variable.
> Then you can keep the use of both the temporary buffer and
> output-buffer.
> 
> Steve Berman

Would you have any hints of why one gets this ?

eval-buffer: End of file during parsing: /home/hagbard/Opstk/lumi.el

Re: Printing comment-start of various modes

[Stephen Berman]

On Tue, 13 Aug 2024 22:10:50 +0000 Heime <heimeborgia@protonmail.com> wrote:

> Would you have any hints of why one gets this ?
>
> eval-buffer: End of file during parsing: /home/hagbard/Opstk/lumi.el

Possibly unbalanced parentheses in the buffer - try `M-x check-parens'.
If that's not the problem, try getting a backtrace, e.g. with `M-x
toggle-debug-on-error' and then evaluating the buffer.

Steve Berman

Re: Printing comment-start of various modes

[Heime]

Sent with Proton Mail secure email.

On Wednesday, August 14th, 2024 at 10:17 AM, Stephen Berman <stephen.berman@gmx.net> wrote:

> On Tue, 13 Aug 2024 22:10:50 +0000 Heime heimeborgia@protonmail.com wrote:
> 
> > Would you have any hints of why one gets this ?
> > 
> > eval-buffer: End of file during parsing: /home/hagbard/Opstk/lumi.el
> 
> 
> Possibly unbalanced parentheses in the buffer - try `M-x check-parens'. If that's not the problem, try getting a backtrace, e.g. with` M-x
> toggle-debug-on-error' and then evaluating the buffer.
> 
> Steve Berman

It was the problem,  unbalanced parentheses in one of the functions