bug#57470: fill-column icon on the ruler is wrongly placed

[uzibalqa]

------ Original Message -------
On Monday, August 29th, 2022 at 4:17 PM, Eli Zaretskii <eliz@gnu.org> wrote:


> > Date: Mon, 29 Aug 2022 14:53:14 +0000
> > From: uzibalqa uzibalqa@proton.me
> > Cc: 57470-done@debbugs.gnu.org
> > 
> > > You need to consult the documentation, yes.
> > 
> > "C-v text-mode-hook" really states that it is
> > "Normal hook run when entering Text mode and many related modes."
> > 
> > "Many related modes", basically tells you nothing.
> 
> 
> It tells me that there are other modes affected.
> 
> You cannot expect every place in the documentation to tell absolutely
> everything, that would make the documentation impossibly large and
> hard to maintain. You need to learn the basics of how to follow links
> and where to find information of certain kinds.
> 
> > I can understand your comment about keeping in mind that every mode for
> > something that looks like a programming language inherits from prog-mode.
> > 
> > But cannot understand any good comment to keep in mind regarding 
> > text-mode-hook.
> 
> 
> From the Emacs manual's node "Text Mode":
> 
> Text mode is a major mode for editing files of text in a human language.
> Files which have names ending in the extension ‘.txt’ are usually opened
> in Text mode (*note Choosing Modes::). To explicitly switch to Text
> mode, type ‘M-x text-mode’.
> [...]
> The following sections describe several major modes that are
> “derived” from Text mode. These derivatives share most of the features
> of Text mode described above. In particular, derivatives of Text mode
> run ‘text-mode-hook’ prior to running their own mode hooks.
> 
> > Emacs should have some automatic mechanism that determines an association 
> > tree
> > on how modes extend to others.
> 
> 
> I don't see why users should care about the hierarchy of modes in
> Emacs. That's something that Emacs developers and maintainers are
> interested in, not users.

They would be of interest to emacs package developers who are at an 
intermediate level
in an elisp context.  Some support functions to make things easier to figure 
out would
help.
 
> Users should have a way of telling whether a given mode is derived
> from another one. For that, you can use the derived-mode-parent
> property:
> 
> M-: (get 'latex-mode 'derived-mode-parent) RET
> => tex-mode
> 
> M-: (get 'tex-mode 'derived-mode-parent) RET
> => text-mode
> 
> Alternatively, in a buffer that is already in latex-mode, you can ask
> whether it inherits from text-mode:
> 
> M-: (derived-mode-p 'text-mode) RET
> => text-mode

Thank you. 
 
> And, of course, the doc string of a mode should tell which hooks it
> runs and which mode is its parent mode. By following the parent-mode
> links you can, if you really want to, go all the way to their
> progenitor.

Running some elisp commands would work better though.