bug#52290: 28.0.90; Undocumented generalized variables

[Phil Sainty]

Many standard generalized variables are not listed in the manual at
(info "(elisp)Setting Generalized Variables") or otherwise documented
as generalized vars so far as I can see.

The omission of `buffer-local-value' was what led me to check these,
as it's utilised by the likes of `electric-indent-local-mode' for
the :variable declaration, which I found confusing until I'd looked
at the code in detail, seen that `setf' was being used on that form,
and found that gv.el did indeed define this as a generalized var
even though the docs didn't mention it.

Comparing the manual node with the contents of gv.el...


In 27.2 there are fairly few omissions from the manual:

- buffer-local-value
- char-table-range
- cond
- cons
- edebug-after
- if
- let
- let*
- logand
- progn


In 28.0.90 the list is huge:

- buffer-file-name
- buffer-local-value
- buffer-modified-p
- buffer-name
- buffer-string
- buffer-substring
- char-table-range
- cond
- cons
- current-buffer
- current-column
- current-global-map
- current-input-mode
- current-local-map
- current-window-configuration
- default-file-modes
- documentation-property
- edebug-after
- eq
- error
- face-background
- face-background-pixmap
- face-font
- face-foreground
- face-underline-p
- file-modes
- frame-height
- frame-parameters
- frame-visible-p
- frame-width
- get-register
- getenv
- global-key-binding
- gv-deref
- if
- let
- let*
- local-key-binding
- logand
- mark
- mark-marker
- marker-position
- mouse-position
- plist-get
- point
- point-marker
- point-max
- point-min
- progn
- read-mouse-position
- screen-height
- screen-width
- selected-frame
- selected-screen
- selected-window
- standard-case-table
- substring
- syntax-table
- visited-file-modtime
- window-height
- window-width
- x-get-secondary-selection

This list of omissions is close to twice the length of the *documented*
cases.

I think the manual should list these, but also at this point I think the
help for any generalized variable should *automatically* state that 
fact,
so that any future omissions are still covered to some extent, and also
so that non-standard generalized vars defined by other libraries will
have some documentation.


-Phil





In GNU Emacs 28.0.90 (build 3, x86_64-pc-linux-gnu, X toolkit, cairo 
version 1.15.10, Xaw scroll bars)
 of 2021-12-03 built on phil-lp
Repository revision: 292ae07e7150a9515b587bd98f9e93ab42c3fb29
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 
11.0.12008000
System Description: Ubuntu 18.04.6 LTS

Configured using:
 'configure --prefix=/home/phil/emacs/28.0/usr/local
 --with-x-toolkit=lucid --without-sound --with-native-compilation'

Configured features:
CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
LCMS2 LIBXML2 MODULES NATIVE_COMP NOTIFY INOTIFY PDUMPER PNG RSVG
SECCOMP THREADS TIFF TOOLKIT_SCROLL_BARS X11 XDBE XIM XPM LUCID ZLIB

Important settings:
  value of $LC_MONETARY: en_NZ.UTF-8
  value of $LC_NUMERIC: en_NZ.UTF-8
  value of $LC_TIME: en_NZ.UTF-8
  value of $LANG: en_NZ.UTF-8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow mail-extr emacsbug message rmc puny dired dired-loaddefs rfc822
mml mml-sec epa derived epg rfc6068 epg-config gnus-util rmail
rmail-loaddefs auth-source eieio eieio-core eieio-loaddefs
password-cache json map text-property-search time-date mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils sort
comp comp-cstr warnings subr-x rx cl-seq cl-macs cl-extra help-mode seq
byte-opt gv cl-loaddefs cl-lib bytecomp byte-compile cconv rect
mule-util jka-compr info iso-transl tooltip eldoc paren electric
uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel
term/x-win x-win term/common-win x-dnd tool-bar dnd fontset image
regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode
prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu
timer select scroll-bar mouse jit-lock font-lock syntax font-core
term/tty-colors frame minibuffer cl-generic cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms
cp51932 hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese composite emoji-zwj charscript charprop case-table
epa-hook jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice
button loaddefs faces cus-face macroexp files window text-properties
overlay sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote threads dbusbind inotify lcms2
dynamic-setting system-font-setting font-render-setting cairo x-toolkit
x multi-tty make-network-process native-compile emacs)

Memory information:
((conses 16 105925 9366)
 (symbols 48 8419 1)
 (strings 32 29142 2540)
 (string-bytes 1 935587)
 (vectors 16 18250)
 (vector-slots 8 355739 12899)
 (floats 8 34 34)
 (intervals 56 826 11)
 (buffers 992 13))