[ESS] file name completion under R

[Stephen Eglen]

 > I do not know whether or not this has been working under any other mode.
 > but under R-mode this hasn't been working for me for at least couple of
 > years on different version of xemacs, emacs  and ESS.
 > The message I get from "tab" is
 > "Wrong type argument: stringp, nil"

...
 > 
 > I guess these two questions can be answered by just fixing ESS M-tab
 > function.  If someonw can give me a clue why I get the above error message
 > maybe I can try and fix it.

It would help us if you try to debug the error; do the following as
listed in the ess manual:
----------------------------------------------------------------------
File: ess.info,  Node: Reporting Bugs,  Next: Mailing Lists,  Prev: Bugs,  Up: Mailing lists/bug reports

Reporting Bugs
==============

   Please send bug reports, suggestions etc. to

   <ESS-bugs at stat.math.ethz.ch>

   The easiest way to do this is within Emacs by typing

   `M-x ess-submit-bug-report'

   This also gives the maintainers valuable information about your
installation which may help us to identify or even fix the bug.

   If Emacs reports an error, backtraces can help us debug the problem.
Type "M-x set-variable RET debug-on-error RET t RET".  Then run the
command that causes the error and you should see a *Backtrace* buffer
containing debug information; send us that buffer.
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 > b) everytime I setwd() in the R buffer, comint-dynamic-complete-filename
 > is kept relative to  the original directory where xemacs was
 > envoked rather than the new directory. Is there a way to do  this?

This came up a few weeks ago; having an automated tracker of the
current directory could be done, but it might be a bit of work.
(e.g. M-x shell does this, but in that case, in your shell you usually
change dirs a lot; my experience with *R* is that I rarely use setwd()
so this feature has not been a priority for me).

Warning: automated directory tracking will have to be optional;
e.g. it may not work for iESS buffers running via M-x ess-remote
when the local and remote machine have different file systems.

Stephen