bug#56816: Missing documentation of function-key-map

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 29 Jul 2022 19:50:35 +0000
> Cc: 56816@debbugs.gnu.org, acm@muc.de
> From: Alan Mackenzie <acm@muc.de>
> 
> > > These are all documentation bugs.
> 
> > Would you please state clearly what exactly is a bug here?
> 
> That there is a reference to function-key-map in that manual page, but
> there is no description of function-key-map whatsoever in the manual.  If
> things are to stay that way, perhaps we could add something like "(not
> documented in this manual.  See the variable's doc string for details.)"
> as a footnote. 

The real description is in "Translation Keymaps" (where you get by
following the cross-reference near local-function-key-map, which
itself is referenced from function-key-map).  I've now added an index
entry for function-key-map in "Translation Keymaps".

> > Specifically, what is missing from the doc string of this variable?
> > Would saying something like "Keymap for bindings of function keys." be
> > enough, or is some other information missing in your opinion, and if
> > so, what?
> 
> That description would be a big improvement.  Perhaps it could also say
> "including modifiers for some keys" or something like that; The
> modifiers, all 7 combinations, are included for each keypad key, but not
> for the other function keys.

The doc string includes a link top local-function-key-map, whose doc
string describes some more.

Given all of the above, what else is missing?  Please be specific.

> > Once we are done with the doc string, we can discuss whether the
> > manual needs any changes in this respect; in general, not every
> > variable must be in the manual, and as long as the doc string is
> > sufficient, we are fine.
> 
> I'll tell you what gave rise to this.  On a proprietary system in my day
> job, typing C-M-a is giving the result M-á, and similarly for the other
> four vowels with C-M-.  This should be relatively straightforward to
> remedy, but I've been struggling with that manual page for two evenings,
> now.  The manual page ("Translation Keymaps") seems to have most of the
> information, but there is little clarity and little redundancy.  I think
> I need to add a binding for M-á to convert it to C-M-a, but in which
> keymap?  There are three keymaps described on the page, but their
> purposes are not entirely clear.  One of them is the one I need, I think.

This doesn't really help, because I don't see how what you describe is
related to the stuff that is or isn't in the documentation.  I'm not
even sure I understand why you think function-key-map is what you need
to investigate, and how are your needs related to what, if anything,
is wrong with or missing from the material in "Translation Keymaps".
"Little clarity and little redundancy" doesn't help me understand what
needs to be done.