bug#57459: Customisation before enabling display-fill-column-indicator-mode

[wilnerthomas]

Aug 28, 2022, 15:02 by eliz@gnu.org:

>> Date: Sun, 28 Aug 2022 16:38:55 +0200 (CEST)
>> From: wilnerthomas@tutanota.com
>> Cc: 57459@debbugs.gnu.org
>>
>> Aug 28, 2022, 14:14 by eliz@gnu.org:
>>
>> > Please show how you tried doing that, starting from "emacs -Q".  There
>> > are many possible ways of customizing face attributes, and we need to
>> > know which one you found not functioning in this case.
>> >
>> I made the following function
>>
>> (defun indicator-attributes ()
>>
>>      (setq display-fill-column-indicator-character ?\u2503)
>>
>>      (set-face-attribute 'fill-column-indicator nil :background "green" 
>> :height 1.0))
>>
>> I have another function to enable global-display-fill-column-indicator-mode
>>
>> (defun  colum-indicator () 
>>      (interactive) (global-display-fill-column-indicator-mode))
>>
>> If I call (indicator-attributes) in my init file, then do "M-x 
>> colum-indicator" in a buffer, I get the old character.
>>
>> But if I change colum-indicator to include (indicator-attributes) after 
>> setting the global mode, I get
>> the correct wider character if I do "M-x colum-indicator" in a buffer.
>>
>> (defun  colum-indicator ()
>>  
>>      (interactive) (global-display-fill-column-indicator-mode) 
>> (indicator-attributes))
>>
>
> It's the same issue as with fill-column:
> display-fill-column-indicator-character is a variable that
> automatically becomes buffer-local when set (see its doc string).  So
> your setq is in effect only for a single buffer: the one in which
> Emacs loads and evaluates the init file.
>
> You should use setq-default instead.
>
> This is not a bug.
>



Thusly I have the same problem because for setq-default,  the new value is seen 
in buffers that do not have their own values for the variable.

But I want to change the value even if buffer has its own value.