bug#18922: 24.3; Not clear how to use TeX input method

[Michael Grünewald]

It is not clear how to use certain combinations for the input method
`tex-input-method'.

The command `describe-input-method` displays the following information:

    key     character(s)  [type a key (sequence) and select one from the
list]
    -------- ------------
    \"A     Ӓ Ǟ Ä

It is however unclear how select one item from this list.

The info page Input Methods [1] does not say anything about it. The info
page
Select an input method[2] contains misleading information. Indeed it
suggests
to use the function M-x quail-show-key to find out how to type a character,
but invoking this function on a ü for instance leads to the sequence "\"u"
which does not produce a ü but a ṳ. Also, the ṳ is first underlined which
suggests that more input can be added to select the right character.
I could nowhere find a clue, which input can be added to select the
right character, that is, a ü.

[1]
https://www.gnu.org/software/emacs/manual/html_node/emacs/Input-Methods.html#Input-Methods
[2]
https://www.gnu.org/software/emacs/manual/html_node/emacs/Select-Input-Method.html#Select-Input-Method

----
In GNU Emacs 24.3.1 (amd64-portbld-freebsd10.0, GTK+ Version 2.24.22)
 of 2014-10-15 on 10amd64-default-job-13
Windowing system distributor `The X.Org Foundation', version 11.0.11204000
Configured using:
 `configure '--localstatedir=/var' '--without-compress-info'
 '--with-dbus' '--with-gconf' '--with-gif' '--with-gnutls'
 '--with-gsettings' '--with-jpeg' '--with-m17n-flt' '--with-imagemagick'
 '--with-libotf' '--with-png' '--with-toolkit-scroll-bars'
 '--with-sound' '--with-rsvg' '--with-sync-input' '--with-tiff'
 '--with-xft' '--with-xim' '--with-xml2' '--with-xpm'
 '--with-x-toolkit=gtk2' '--with-x' '--x-libraries=/usr/local/lib'
 '--x-includes=/usr/local/include' '--prefix=/usr/local'
 '--mandir=/usr/local/man' '--infodir=/usr/local/share/emacs/info/'
 '--build=amd64-portbld-freebsd10.0'
 'build_alias=amd64-portbld-freebsd10.0' 'CC=cc' 'CFLAGS=-O2 -pipe
 -fno-strict-aliasing' 'LDFLAGS= -L/usr/local/lib
 -Wl,-rpath=/usr/lib:/usr/local/lib' 'LIBS='
 'CPPFLAGS=-I/usr/local/include' 'CPP=cpp''

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  shell-dirtrack-mode: t
  global-whitespace-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<escape> x s e t SPC i n <tab> <return> T e X <return>
\ " u <tab> 7 <backspace> <backspace> \ " u <f1> <C-f1>
\ " u h <backspace> <backspace> <backspace> \ u <tab>
<tab> <tab> a a <backspace> <backspace> \ u a 7 <backspace>
<backspace> <escape> x r e p o t <backspace> <backspace>
o r t <tab> <return>

Recent messages:
Loading /home/michael/.emacs.d/custom.el (source)...done
(lambda (p) ...) quoted with ' rather than with #'
For information about GNU Emacs and the GNU system, type C-h C-a.
Loading quail/latin-ltx...done
You can run the command `set-input-method' with C-x RET C-\
delete-backward-char: Text is read-only

Load-path shadows:
~/share/emacs/site-lisp/noweb-mode hides
/usr/local/share/emacs/site-lisp/noweb-mode

Features:
(shadow sort mail-extr emacsbug message idna format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mailabbrev gmm-utils mailheader
sendmail mail-utils cus-start cus-load quail help-mode trac-wiki
warnings advice help-fns advice-preload xml-rpc cl-macs gv cl cl-lib
timezone url-http tls url url-proxy url-privacy url-expand url-methods
url-history mailcap url-auth mail-parse rfc2231 rfc2047 rfc2045
ietf-drums url-cookie url-domsuf url-util url-parse auth-source eieio
byte-opt bytecomp byte-compile cconv gnus-util mm-util mail-prsvr
password-cache url-gw url-vars xml tex-mode edmacro kmacro emake
css-mode ocamldebug derived shell pcomplete caml tuareg speedbar
sb-image ezimage dframe compile comint ansi-color ring smie easymenu
psgml-startup time-date whitespace tooltip ediff-hook vc-hooks
lisp-float-type mwheel x-win x-dnd tool-bar dnd fontset image regexp-opt
fringe tabulated-list newcomment lisp-mode register page menu-bar
rfn-eshadow timer select scroll-bar mouse jit-lock font-lock syntax
facemenu font-core frame cham georgian utf-8-lang misc-lang vietnamese
tibetan thai tai-viet lao korean japanese hebrew greek romanian slovak
czech european ethiopic indian cyrillic chinese case-table epa-hook
jka-cmpr-hook help simple abbrev minibuffer loaddefs button faces
cus-face macroexp files text-properties overlay sha1 md5 base64 format
env code-pages mule custom widget hashtable-print-readable backquote
make-network-process dbusbind dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty emacs)

-- 
Michael