Highlight tabulated and trailing whitespace

Highlight tabulated and trailing whitespace

[steve-humphreys]

I would like to highlight tabulated and trailing whitespace, using the following
code on a dark background.  The highlighting is not working.  I might also be
changing tabs with spaced but do not what command I had used.

(defun whitesp-highlight ()
  "Highlights whitespace."

  (require 'whitespace)
  (setq-local show-trailing-whitespace t)

  (whitespace-mode)
  (setq whitespace-style '(face tabs))
  (modify-face whitespace-tab nil "#000000")

  ;; Highlights tabulator regions
  (setq whitespace-style '(tabs tab-mark))
  (global-whitespace-mode 1) )

Re: Highlight tabulated and trailing whitespace

[Emanuel Berg via Users list for the GNU Emacs text editor]

steve-humphreys wrote:

> I would like to highlight tabulated and trailing whitespace, using the following
> code on a dark background.  The highlighting is not working.  I might also be
> changing tabs with spaced but do not what command I had used.
>
> (defun whitesp-highlight ()
>   "Highlights whitespace."
>
>   (require 'whitespace)
>   (setq-local show-trailing-whitespace t)
>
>   (whitespace-mode)
>   (setq whitespace-style '(face tabs))
>   (modify-face whitespace-tab nil "#000000")
>
>   ;; Highlights tabulator regions
>   (setq whitespace-style '(tabs tab-mark))
>   (global-whitespace-mode 1) )

(setq show-trailing-whitespace t)


-- 
underground experts united
http://user.it.uu.se/~embe8573
https://dataswamp.org/~incal

Re: Highlight tabulated and trailing whitespace

[steve-humphreys]

> Sent: Monday, December 28, 2020 at 10:20 AM
> From: "Emanuel Berg via Users list for the GNU Emacs text editor" <help-gnu-emacs@gnu.org>
> To: help-gnu-emacs@gnu.org
> Subject: Re: Highlight tabulated and trailing whitespace
>
> steve-humphreys wrote:
>
> > I would like to highlight tabulated and trailing whitespace, using the following
> > code on a dark background.  The highlighting is not working.  I might also be
> > changing tabs with spaced but do not what command I had used.
> >
> > (defun whitesp-highlight ()
> >   "Highlights whitespace."
> >
> >   (require 'whitespace)
> >   (setq-local show-trailing-whitespace t)
> >
> >   (whitespace-mode)
> >   (setq whitespace-style '(face tabs))
> >   (modify-face whitespace-tab nil "#000000")
> >
> >   ;; Highlights tabulator regions
> >   (setq whitespace-style '(tabs tab-mark))
> >   (global-whitespace-mode 1) )
>
> (setq show-trailing-whitespace t)
>

Is "show-trailing-whitespace" buffer local?

> --
> underground experts united
> http://user.it.uu.se/~embe8573
> https://dataswamp.org/~incal
>
>
>

Re: Highlight tabulated and trailing whitespace

[2QdxY4RzWzUUiLuE]

On 2020-12-28 at 05:56:43 +0100,
steve-humphreys@gmx.com wrote:

> Is "show-trailing-whitespace" buffer local?

According to it's documentation, it is.  And even if it weren't, you
could change it.  See make-variable-buffer-local.

Re: Highlight tabulated and trailing whitespace

[steve-humphreys]

What can I do to show tabs like I am doing with show-trailing-whitespace?

> Sent: Monday, December 28, 2020 at 10:20 AM
> From: "Emanuel Berg via Users list for the GNU Emacs text editor" <help-gnu-emacs@gnu.org>
> To: help-gnu-emacs@gnu.org
> Subject: Re: Highlight tabulated and trailing whitespace
>
> steve-humphreys wrote:
>
> > I would like to highlight tabulated and trailing whitespace, using the following
> > code on a dark background.  The highlighting is not working.  I might also be
> > changing tabs with spaced but do not what command I had used.
> >
> > (defun whitesp-highlight ()
> >   "Highlights whitespace."
> >
> >   (require 'whitespace)
> >   (setq-local show-trailing-whitespace t)
> >
> >   (whitespace-mode)
> >   (setq whitespace-style '(face tabs))
> >   (modify-face whitespace-tab nil "#000000")
> >
> >   ;; Highlights tabulator regions
> >   (setq whitespace-style '(tabs tab-mark))
> >   (global-whitespace-mode 1) )
>
> (setq show-trailing-whitespace t)
>
>
> --
> underground experts united
> http://user.it.uu.se/~embe8573
> https://dataswamp.org/~incal
>
>
>

Re: Highlight tabulated and trailing whitespace

[steve-humphreys]

I have tried to show tab marks, but the following commands are confusing me.  One can
use a backgrouund colour and introduce a tab mark.  But I have no idea how to achieve
them.

  (setq whitespace-style '(face tabs))
  (setq whitespace-style '(tabs tab-mark))



> Sent: Monday, December 28, 2020 at 10:42 AM
> From: steve-humphreys@gmx.com
> To: moasenwood@zoho.eu
> Cc: help-gnu-emacs@gnu.org
> Subject: Re: Highlight tabulated and trailing whitespace
>
> What can I do to show tabs like I am doing with show-trailing-whitespace?
>
> > Sent: Monday, December 28, 2020 at 10:20 AM
> > From: "Emanuel Berg via Users list for the GNU Emacs text editor" <help-gnu-emacs@gnu.org>
> > To: help-gnu-emacs@gnu.org
> > Subject: Re: Highlight tabulated and trailing whitespace
> >
> > steve-humphreys wrote:
> >
> > > I would like to highlight tabulated and trailing whitespace, using the following
> > > code on a dark background.  The highlighting is not working.  I might also be
> > > changing tabs with spaced but do not what command I had used.
> > >
> > > (defun whitesp-highlight ()
> > >   "Highlights whitespace."
> > >
> > >   (require 'whitespace)
> > >   (setq-local show-trailing-whitespace t)
> > >
> > >   (whitespace-mode)
> > >   (setq whitespace-style '(face tabs))
> > >   (modify-face whitespace-tab nil "#000000")
> > >
> > >   ;; Highlights tabulator regions
> > >   (setq whitespace-style '(tabs tab-mark))
> > >   (global-whitespace-mode 1) )
> >
> > (setq show-trailing-whitespace t)
> >
> >
> > --
> > underground experts united
> > http://user.it.uu.se/~embe8573
> > https://dataswamp.org/~incal
> >
> >
> >
>
>

Re: Highlight tabulated and trailing whitespace

[Emanuel Berg via Users list for the GNU Emacs text editor]

steve-humphreys wrote:

> I have tried to show tab marks, but the following commands
> are confusing me. One can use a backgrouund colour and
> introduce a tab mark. But I have no idea how to
> achieve them.
>
>   (setq whitespace-style '(face tabs))

Then just set the `whitespace-tab' face, to some face other
than what the default face has,

(insert "\t <-- this is a tab")

and enable the mode.

-- 
underground experts united
http://user.it.uu.se/~embe8573
https://dataswamp.org/~incal

Re: Highlight tabulated and trailing whitespace

[steve-humphreys]

Have tried the following two lines to no effect

(require 'whitespace)
(whitespace-mode)

But then if I use "H-k" to toggle, the command works.  What is happening???

(global-set-key (kbd "H-k") 'whitespace-mode)




> Sent: Monday, December 28, 2020 at 1:11 PM
> From: "Emanuel Berg via Users list for the GNU Emacs text editor" <help-gnu-emacs@gnu.org>
> To: help-gnu-emacs@gnu.org
> Subject: Re: Highlight tabulated and trailing whitespace
>
> steve-humphreys wrote:
>
> > I have tried to show tab marks, but the following commands
> > are confusing me. One can use a backgrouund colour and
> > introduce a tab mark. But I have no idea how to
> > achieve them.
> >
> >   (setq whitespace-style '(face tabs))
>
> Then just set the `whitespace-tab' face, to some face other
> than what the default face has,
>
> (insert "\t <-- this is a tab")
>
> and enable the mode.
>
> --
> underground experts united
> http://user.it.uu.se/~embe8573
> https://dataswamp.org/~incal
>
>
>

Re: Highlight tabulated and trailing whitespace

[Michael Heerdegen]

steve-humphreys@gmx.com writes:

> Have tried the following two lines to no effect
>
> (require 'whitespace)
> (whitespace-mode)

What does "have tried" mean?

Michael.

Re: Highlight tabulated and trailing whitespace

[Óscar Fuentes]

steve-humphreys@gmx.com writes:

> Have tried the following two lines to no effect
>
> (require 'whitespace)
> (whitespace-mode)

In a buffer, just:

M-x whitespace-mode

For enabling it automatically when you open certain type of files, use a
major mode hook. For instance:

(add-hook 'prog-mode-hook #'whitespace-mode)

Will activate whitespace-mode in all programming language modes.

Re: Highlight tabulated and trailing whitespace

[steve-humphreys]

I cannot understand why the following code is giving me a lisp error.

(defun display-cycle ()
  "Toggle Display-Line-Numbers mode in all buffers."
  (interactive)

  (let ((n display-cycle-state))

    (pcase n
      (1 (whitespace-mode)
	 (setq-local display-cycle-state 2))

      (2 (ruler-mode 0)
	 (setq line-number-mode nil)
	 (setq column-number-mode nil)
	 (global-display-line-numbers-mode)
	 (setq-local display-cycle-state 3))

      (_ (ruler-mode 1)
	 (setq line-number-mode t)
	 (setq column-number-mode t)
	 (global-display-line-numbers-mode)
	 (setq-local display-cycle-state 1))) ))





> Sent: Monday, December 28, 2020 at 2:10 PM
> From: steve-humphreys@gmx.com
> To: moasenwood@zoho.eu
> Cc: help-gnu-emacs@gnu.org
> Subject: Re: Highlight tabulated and trailing whitespace
>
> Have tried the following two lines to no effect
>
> (require 'whitespace)
> (whitespace-mode)
>
> But then if I use "H-k" to toggle, the command works.  What is happening???
>
> (global-set-key (kbd "H-k") 'whitespace-mode)
>
>
>
>
> > Sent: Monday, December 28, 2020 at 1:11 PM
> > From: "Emanuel Berg via Users list for the GNU Emacs text editor" <help-gnu-emacs@gnu.org>
> > To: help-gnu-emacs@gnu.org
> > Subject: Re: Highlight tabulated and trailing whitespace
> >
> > steve-humphreys wrote:
> >
> > > I have tried to show tab marks, but the following commands
> > > are confusing me. One can use a backgrouund colour and
> > > introduce a tab mark. But I have no idea how to
> > > achieve them.
> > >
> > >   (setq whitespace-style '(face tabs))
> >
> > Then just set the `whitespace-tab' face, to some face other
> > than what the default face has,
> >
> > (insert "\t <-- this is a tab")
> >
> > and enable the mode.
> >
> > --
> > underground experts united
> > http://user.it.uu.se/~embe8573
> > https://dataswamp.org/~incal
> >
> >
> >
>
>

Re: Highlight tabulated and trailing whitespace

[steve-humphreys]

The error is

Debugger entered--Lisp error: (void-variable display-cycle-state)
  (let ((n display-cycle-state))

> I cannot understand why the following code is giving me a lisp error.
>
> (defun display-cycle ()
>   "Toggle Display-Line-Numbers mode in all buffers."
>   (interactive)
>
>   (let ((n display-cycle-state))
>
>     (pcase n
>       (1 (whitespace-mode)
> 	 (setq-local display-cycle-state 2))
>
>       (2 (ruler-mode 0)
> 	 (setq line-number-mode nil)
> 	 (setq column-number-mode nil)
> 	 (global-display-line-numbers-mode)
> 	 (setq-local display-cycle-state 3))
>
>       (_ (ruler-mode 1)
> 	 (setq line-number-mode t)
> 	 (setq column-number-mode t)
> 	 (global-display-line-numbers-mode)
> 	 (setq-local display-cycle-state 1))) ))
>
>
>
>
>
> > Sent: Monday, December 28, 2020 at 2:10 PM
> > From: steve-humphreys@gmx.com
> > To: moasenwood@zoho.eu
> > Cc: help-gnu-emacs@gnu.org
> > Subject: Re: Highlight tabulated and trailing whitespace
> >
> > Have tried the following two lines to no effect
> >
> > (require 'whitespace)
> > (whitespace-mode)
> >
> > But then if I use "H-k" to toggle, the command works.  What is happening???
> >
> > (global-set-key (kbd "H-k") 'whitespace-mode)
> >
> >
> >
> >
> > > Sent: Monday, December 28, 2020 at 1:11 PM
> > > From: "Emanuel Berg via Users list for the GNU Emacs text editor" <help-gnu-emacs@gnu.org>
> > > To: help-gnu-emacs@gnu.org
> > > Subject: Re: Highlight tabulated and trailing whitespace
> > >
> > > steve-humphreys wrote:
> > >
> > > > I have tried to show tab marks, but the following commands
> > > > are confusing me. One can use a backgrouund colour and
> > > > introduce a tab mark. But I have no idea how to
> > > > achieve them.
> > > >
> > > >   (setq whitespace-style '(face tabs))
> > >
> > > Then just set the `whitespace-tab' face, to some face other
> > > than what the default face has,
> > >
> > > (insert "\t <-- this is a tab")
> > >
> > > and enable the mode.
> > >
> > > --
> > > underground experts united
> > > http://user.it.uu.se/~embe8573
> > > https://dataswamp.org/~incal
> > >
> > >
> > >
> >
> >
>

RE: Highlight tabulated and trailing whitespace

[Drew Adams]

Where is that variable supposed to come from?
I don't see it with vanilla Emacs 26 (`emacs -Q').

Perhaps you need to load some library first, so
it becomes defined.

And perhaps it's actually a function?  If not,
why do you bother to bind it to `n', which isn't
modified anywhere?  Is it only to have a shorter
variable name when you refer to the value (i.e.,
instead of referring to `display-cycle-stae')?
Not clear to me what you're trying to do.

> Debugger entered--Lisp error: (void-variable display-cycle-state)
>   (let ((n display-cycle-state))
> 
> > (let ((n display-cycle-state))
> >   (pcase n ...

Re: RE: Highlight tabulated and trailing whitespace

[steve-humphreys]

I thought that if it was not defined, it would go to the any expval match _
when the variable is then set up as buffer-local.

When I use

(defvar display-cycle-state 0) things do work.

> Sent: Monday, December 28, 2020 at 10:25 PM
> From: "Drew Adams" <drew.adams@oracle.com>
> To: steve-humphreys@gmx.com
> Cc: help-gnu-emacs@gnu.org, moasenwood@zoho.eu
> Subject: RE: Highlight tabulated and trailing whitespace
>
> Where is that variable supposed to come from?
> I don't see it with vanilla Emacs 26 (`emacs -Q').
>
> Perhaps you need to load some library first, so
> it becomes defined.
>
> And perhaps it's actually a function?  If not,
> why do you bother to bind it to `n', which isn't
> modified anywhere?  Is it only to have a shorter
> variable name when you refer to the value (i.e.,
> instead of referring to `display-cycle-stae')?
> Not clear to me what you're trying to do.
>
> > Debugger entered--Lisp error: (void-variable display-cycle-state)
> >   (let ((n display-cycle-state))
> >
> > > (let ((n display-cycle-state))
> > >   (pcase n ...
>