GNU bug report logs - #78579
30.0.92; Global variant of delete-trailing-whitespace-mode

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Jake <jforst.mailman <at> gmail.com>
To: bug-gnu-emacs <at> gnu.org
Cc: Stefan Monnier <monnier <at> iro.umontreal.ca>
Subject: 30.0.92; Global variant of delete-trailing-whitespace-mode
Date: Sat, 24 May 2025 13:48:44 +0000

[Message part 1 (text/plain, inline)]

`delete-trailing-whitespace-mode` was introduced in commit 8a19c249f81.
Should there also be a `global-delete-trailing-whitespace-mode`?
This would allow
  (global-delete-trailing-whitespace-mode 1)
and turning it off in an individual buffer with
  (delete-trailing-whitespace-mode -1)

Thanks
Jake

[Message part 2 (text/html, inline)]

Message #8 received at 78579 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Jake <jforst.mailman <at> gmail.com>
Cc: 78579 <at> debbugs.gnu.org
Subject: Re: 30.0.92; Global variant of delete-trailing-whitespace-mode
Date: Sat, 24 May 2025 11:14:24 -0400

> `delete-trailing-whitespace-mode` was introduced in commit 8a19c249f81.
> Should there also be a `global-delete-trailing-whitespace-mode`?
> This would allow
>   (global-delete-trailing-whitespace-mode 1)
> and turning it off in an individual buffer with
>   (delete-trailing-whitespace-mode -1)

To define such a mode, we'll need to know when to enable it and when
not: I'd be surprised if adding `delete-trailing-whitespace` globally
to `before-save-hook` doesn't cause problems in various circumstances.

I don't have enough experience with that, so I'll let others decide if
and how to do it.


        Stefan

Message #11 received at 78579 <at> debbugs.gnu.org (full text, mbox):

From: Ship Mints <shipmints <at> gmail.com>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: Jake <jforst.mailman <at> gmail.com>, 78579 <at> debbugs.gnu.org
Subject: Re: bug#78579: 30.0.92;
 Global variant of delete-trailing-whitespace-mode
Date: Sat, 24 May 2025 11:23:13 -0400

[Message part 1 (text/plain, inline)]

On Sat, May 24, 2025 at 11:15 AM Stefan Monnier via Bug reports for GNU
Emacs, the Swiss army knife of text editors <bug-gnu-emacs <at> gnu.org> wrote:

> > `delete-trailing-whitespace-mode` was introduced in commit 8a19c249f81.
> > Should there also be a `global-delete-trailing-whitespace-mode`?
> > This would allow
> >   (global-delete-trailing-whitespace-mode 1)
> > and turning it off in an individual buffer with
> >   (delete-trailing-whitespace-mode -1)
>
> To define such a mode, we'll need to know when to enable it and when
> not: I'd be surprised if adding `delete-trailing-whitespace` globally
> to `before-save-hook` doesn't cause problems in various circumstances.
>
> I don't have enough experience with that, so I'll let others decide if
> and how to do it.
>

FWIW, this is how I manage that and even then I might enable it for
markdown mode:

(defun my/before-save-hook ()
  "Delete trailing white space before saving a buffer, except
`markdown-mode'."
  (unless (derived-mode-p 'markdown-mode)
    (delete-trailing-whitespace)))
(add-hook 'before-save-hook #'my/before-save-hook)

I suppose an exclusion mode list or some other conditionals could be baked
into the mode.

[Message part 2 (text/html, inline)]

Message #14 received at 78579 <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: jforst.mailman <at> gmail.com, 78579 <at> debbugs.gnu.org
Subject: Re: bug#78579: 30.0.92;
 Global variant of delete-trailing-whitespace-mode
Date: Sat, 24 May 2025 18:50:16 +0300

> Cc: 78579 <at> debbugs.gnu.org
> Date: Sat, 24 May 2025 11:14:24 -0400
> From:  Stefan Monnier via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs <at> gnu.org>
> 
> > `delete-trailing-whitespace-mode` was introduced in commit 8a19c249f81.
> > Should there also be a `global-delete-trailing-whitespace-mode`?
> > This would allow
> >   (global-delete-trailing-whitespace-mode 1)
> > and turning it off in an individual buffer with
> >   (delete-trailing-whitespace-mode -1)
> 
> To define such a mode, we'll need to know when to enable it and when
> not: I'd be surprised if adding `delete-trailing-whitespace` globally
> to `before-save-hook` doesn't cause problems in various circumstances.
> 
> I don't have enough experience with that, so I'll let others decide if
> and how to do it.

I share the fears expressed by Stefan.  I think that such a global
mode would be more dangerous than it's useful.  After all, it's easy
to add the activation of the local minor mode to mode-hook of any
modes one wants.

Message #19 received at 78579-done <at> debbugs.gnu.org (full text, mbox):

From: Jake <jforst.mailman <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>, 78579-done <at> debbugs.gnu.org
Cc: Stefan Monnier <monnier <at> iro.umontreal.ca>
Subject: Re: bug#78579: 30.0.92;
 Global variant of delete-trailing-whitespace-mode
Date: Sun, 25 May 2025 19:37:29 +0930

[Message part 1 (text/plain, inline)]

Thanks for explaining.  Closing

On Sun, 25 May 2025 at 1:20 am, Eli Zaretskii <eliz <at> gnu.org> wrote:

> > Cc: 78579 <at> debbugs.gnu.org
> > Date: Sat, 24 May 2025 11:14:24 -0400
> > From:  Stefan Monnier via "Bug reports for GNU Emacs,
> >  the Swiss army knife of text editors" <bug-gnu-emacs <at> gnu.org>
> >
> > > `delete-trailing-whitespace-mode` was introduced in commit 8a19c249f81.
> > > Should there also be a `global-delete-trailing-whitespace-mode`?
> > > This would allow
> > >   (global-delete-trailing-whitespace-mode 1)
> > > and turning it off in an individual buffer with
> > >   (delete-trailing-whitespace-mode -1)
> >
> > To define such a mode, we'll need to know when to enable it and when
> > not: I'd be surprised if adding `delete-trailing-whitespace` globally
> > to `before-save-hook` doesn't cause problems in various circumstances.
> >
> > I don't have enough experience with that, so I'll let others decide if
> > and how to do it.
>
> I share the fears expressed by Stefan.  I think that such a global
> mode would be more dangerous than it's useful.  After all, it's easy
> to add the activation of the local minor mode to mode-hook of any
> modes one wants.
>

[Message part 2 (text/html, inline)]

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