[ESS] German umlaute in ESS, Emacs & R

[Martin Maechler]

>>>>> "es" == enno sandkasten <enno_sandkasten at arcor.de>
>>>>>     on Thu, 31 Jul 2008 11:17:38 +0200 (CEST) writes:

    es> Hi list,
    es> I use GNU Emacs 22.2.1 (i386-mingw-nt5.1.2600) of 2008-03-26 on Windows XP and ESS Version 5.3.7, both downloaded from http://vgoulet.act.ulaval.ca/en/ressources/emacs/, and R version 2.7.1 for Windows.

    es> My problem is that Emacs cannot handle german umlaute as R variable names:

    >> ä <- 3
    es> Error: unexpected input in "\201"

    es> This does not occur in RGui.exe. I think this is more an emacs than ess problem, but maybe there are any suggestions.

Yes, it seems an Emacs rather than ESS problem, also visible on
Linux.
I can reproduce the problem also by starting R from the *shell* (M-x
shell) buffer, hence it's not related to ESS,
but most probably related to how emacs uses the 'comint-*'
functions to communicate with the "inferior" process.
I see the problem in all cases (within Emacs),
both when then emacs-input (and -output method of the process is set to 
utf-8 or iso-latin-1 respectively {C-x RET p ...; 
C-x RET C-h shows you the list} and both for my default unicode
utf-8 locale and with the C locale.

OTOH, I can use 'ä' in the emacs shell more less fine:
I can use it for input, but it does not correctly render for
output.

  $ touch ä   << shows Umlaut
  $ ls -l ä   << shows Umlaut
  -rw-r--r-- 1 maechler sfsstaff 0 Jul 31 18:25 ? << shows question mark
  "?" (
  $ . /u/sfs/adm/locale-deCH-UTF8.sh
  $ ls -l ä <
  -rw-r--r-- 1 maechler sfsstaff 0 Jul 31 18:25 ?
  $ echo BLA >> ä
  $ ls -l ä
  -rw-r--r-- 1 maechler sfsstaff 4 Jul 31 18:25 ?


BTW: I would never use non-ASCII characters in variable names,
      but that's really a separate issue;
 and I can imagine people having "good" reasons to do so.
 Note that it *can* dangerous: I see different files created by
 'touch ä' depending on the locale (ISO-latin-1 vs Unicode UTF-8)


Martin