c-update-modeline format for c-block-comment-flag

c-update-modeline format for c-block-comment-flag

[Andy Moreton]

Hi,

The handling of c-block-comment-flag in c-update-modeline is
unfortunate:

(defun c-update-modeline ()
  (let ((fmt (format "/%s%s%s%s%s"
		     (if c-block-comment-flag "*" "/")
		     (if c-electric-flag "l" "")
		     (if (and c-electric-flag c-auto-newline)
			 "a" "")
		     (if c-hungry-delete-key "h" "")
		     (if (and
			  ;; (cc-)subword might not be loaded.
			  (boundp 'c-subword-mode)
			  (symbol-value 'c-subword-mode))
                         ;; FIXME: subword-mode already comes with its
                         ;; own lighter!
			 "w"
		       "")))

This fixed "/" in the modeline string forces this submode lighter to be
always present, and prevents the diminish or delight packages from being
able to remove or replace this lighter.

Can this be fixed for emacs-26 ?

   AndyM

Re: c-update-modeline format for c-block-comment-flag

[Eli Zaretskii]

> From: Andy Moreton <andrewjmoreton@gmail.com>
> Date: Fri, 13 Oct 2017 11:24:03 +0100
> 
> (defun c-update-modeline ()
>   (let ((fmt (format "/%s%s%s%s%s"
> 		     (if c-block-comment-flag "*" "/")
> 		     (if c-electric-flag "l" "")
> 		     (if (and c-electric-flag c-auto-newline)
> 			 "a" "")
> 		     (if c-hungry-delete-key "h" "")
> 		     (if (and
> 			  ;; (cc-)subword might not be loaded.
> 			  (boundp 'c-subword-mode)
> 			  (symbol-value 'c-subword-mode))
>                          ;; FIXME: subword-mode already comes with its
>                          ;; own lighter!
> 			 "w"
> 		       "")))
> 
> This fixed "/" in the modeline string forces this submode lighter to be
> always present, and prevents the diminish or delight packages from being
> able to remove or replace this lighter.
> 
> Can this be fixed for emacs-26 ?

Depends on the fix and on when this was introduced.

Re: c-update-modeline format for c-block-comment-flag

[Alan Mackenzie]

Hello, Andy.

On Fri, Oct 13, 2017 at 11:24:03 +0100, Andy Moreton wrote:
> Hi,

> The handling of c-block-comment-flag in c-update-modeline is
> unfortunate:

> (defun c-update-modeline ()
>   (let ((fmt (format "/%s%s%s%s%s"
> 		     (if c-block-comment-flag "*" "/")
> 		     (if c-electric-flag "l" "")
> 		     (if (and c-electric-flag c-auto-newline)
> 			 "a" "")
> 		     (if c-hungry-delete-key "h" "")
> 		     (if (and
> 			  ;; (cc-)subword might not be loaded.
> 			  (boundp 'c-subword-mode)
> 			  (symbol-value 'c-subword-mode))
>                          ;; FIXME: subword-mode already comes with its
>                          ;; own lighter!
> 			 "w"
> 		       "")))

> This fixed "/" in the modeline string forces this submode lighter to be
> always present, .....

How?  What mechanism do you mean?

> .... and prevents the diminish or delight packages from being able to
> remove or replace this lighter.

I'm not familiar with either of these packages.  How does the fixed "/"
prevent these packages from working?

> Can this be fixed for emacs-26 ?

What do you mean by "fixed", here?  What do you want to do with this
portion of the mode line, exactly?

>    AndyM

-- 
Alan Mackenzie (Nuremberg, Germany).

Re: c-update-modeline format for c-block-comment-flag

[Andy Moreton]

On Fri 13 Oct 2017, Alan Mackenzie wrote:

> Hello, Andy.
>
> On Fri, Oct 13, 2017 at 11:24:03 +0100, Andy Moreton wrote:
>> Hi,
>
>> The handling of c-block-comment-flag in c-update-modeline is
>> unfortunate:
>
>> (defun c-update-modeline ()
>>   (let ((fmt (format "/%s%s%s%s%s"
>> 		     (if c-block-comment-flag "*" "/")
>> 		     (if c-electric-flag "l" "")
>> 		     (if (and c-electric-flag c-auto-newline)
>> 			 "a" "")
>> 		     (if c-hungry-delete-key "h" "")
>> 		     (if (and
>> 			  ;; (cc-)subword might not be loaded.
>> 			  (boundp 'c-subword-mode)
>> 			  (symbol-value 'c-subword-mode))
>>                          ;; FIXME: subword-mode already comes with its
>>                          ;; own lighter!
>> 			 "w"
>> 		       "")))
>
>> This fixed "/" in the modeline string forces this submode lighter to be
>> always present, .....
>
> How?  What mechanism do you mean?

The lighter for c-mode changed from "C" to "C//" or "C/*".
The lighter for c++-mode changed from "C++" to "C++//" or "C++/*".

Both of these changes do not allow me to omit the lighter, or to change
it to something else without replacing the implementation of
c-update-modeline.

>> .... and prevents the diminish or delight packages from being able to
>> remove or replace this lighter.
>
> I'm not familiar with either of these packages.  How does the fixed "/"
> prevent these packages from working?

I've not found a way to get them to work with varying strings. 

>> Can this be fixed for emacs-26 ?
>
> What do you mean by "fixed", here?  What do you want to do with this
> portion of the mode line, exactly?

Allow the "//" or "/*" to be omitted entirely, or replaced with a
different string as the lighter for those sub-modes.

    AndyM

Re: c-update-modeline format for c-block-comment-flag

[Alan Mackenzie]

Hello again, Andy.

On Fri, Oct 13, 2017 at 16:20:48 +0100, Andy Moreton wrote:
> On Fri 13 Oct 2017, Alan Mackenzie wrote:

> > Hello, Andy.

> > On Fri, Oct 13, 2017 at 11:24:03 +0100, Andy Moreton wrote:
> >> Hi,

> >> The handling of c-block-comment-flag in c-update-modeline is
> >> unfortunate:

> >> (defun c-update-modeline ()
> >>   (let ((fmt (format "/%s%s%s%s%s"
> >> 		     (if c-block-comment-flag "*" "/")
> >> 		     (if c-electric-flag "l" "")
> >> 		     (if (and c-electric-flag c-auto-newline)
> >> 			 "a" "")
> >> 		     (if c-hungry-delete-key "h" "")
> >> 		     (if (and
> >> 			  ;; (cc-)subword might not be loaded.
> >> 			  (boundp 'c-subword-mode)
> >> 			  (symbol-value 'c-subword-mode))
> >>                          ;; FIXME: subword-mode already comes with its
> >>                          ;; own lighter!
> >> 			 "w"
> >> 		       "")))

> >> This fixed "/" in the modeline string forces this submode lighter to be
> >> always present, .....

> > How?  What mechanism do you mean?

> The lighter for c-mode changed from "C" to "C//" or "C/*".
> The lighter for c++-mode changed from "C++" to "C++//" or "C++/*".

The lighter for these modes has "always" included a "/" followed by
status letters, where "always" means for at least 15 years.  The "*" or
second "/" is a recent innovation to indicate the current default form of
comments.

> Both of these changes do not allow me to omit the lighter, or to change
> it to something else without replacing the implementation of
> c-update-modeline.

The form of this section of the mode line matches the regexp
"/[/*]l?a?h?w?".  Perhaps one of these packages could be enhanced to
handle regexps, if they can't already do so.

> >> .... and prevents the diminish or delight packages from being able to
> >> remove or replace this lighter.

> > I'm not familiar with either of these packages.  How does the fixed "/"
> > prevent these packages from working?

> I've not found a way to get them to work with varying strings. 

How about enhancing one of them to do so?

> >> Can this be fixed for emacs-26 ?

> > What do you mean by "fixed", here?  What do you want to do with this
> > portion of the mode line, exactly?

> Allow the "//" or "/*" to be omitted entirely, or replaced with a
> different string as the lighter for those sub-modes.

With the first of my questions, I was really asking you how you want CC
Mode to be fixed.  I think I now understand that you want to replace the
string.

>     AndyM

-- 
Alan Mackenzie (Nuremberg, Germany).

Re: c-update-modeline format for c-block-comment-flag

[Andy Moreton]

On Fri 13 Oct 2017, Alan Mackenzie wrote:

> The lighter for these modes has "always" included a "/" followed by
> status letters, where "always" means for at least 15 years.  The "*" or
> second "/" is a recent innovation to indicate the current default form of
> comments.

Most of those letters are disabled in my usage, so I notice it less.

The mode reported by Dired has changed - that used to be "C" or "C++"
in 25.3, but is now e.g. "C/*" or "C++//".

It would perhaps be more flexible to configure these lighters as minor
modes, e.g. to show the c style I have:

  (define-minor-mode c-show-style-mode
    "Minor mode to display the C indentation style in the mode line."
    :lighter (c-show-style-mode
              (" " (:propertize c-indentation-style face italic))))

  (defun ajm:c-mode-common-init ()
    (c-show-style-mode 1))
  (add-hook 'c-mode-common-hook 'ajm:c-mode-common-init)


    AndyM