[ESS-bugs] OOps! ESS partly fails in non-English locales!

[Martin Maechler]

>>>>> "StEgl" == Stephen Eglen <S.J.Eglen at damtp.cam.ac.uk>
>>>>>     on Tue, 2 Aug 2005 12:31:40 +0100 writes:

    StEgl> thanks for follow up Martin.

    >> One thing: May be it is not "more problematic" than the problem I
    >> reported.  The "only" mistake is the mini-buffer message "Not a
    >> syntax error", but then one at least gets to see a relatively
    >> simply to understand message.

    StEgl> Yes, agree - sorry, "problematic" was a bad choice of wording from me.

    StEgl> I can fix the regexp for this particular error:

    StEgl> Error in parse(file, n = -1, NULL, "?") : syntax error on line 3

    StEgl> perhaps by a regexp searching for

    StEgl> syntax error on line [line number]

    StEgl> but is that likely to be good enough for catching all R errors?

not all R errors for sure.

But for C-c C-l, we know that R (and S-plus) uses source(),
so we have to think about the errors that happen from source().

There, the syntax error is really a special interesting case,
because that one can be pointed to by a line number.
For R, it will always happen from
    .Internal(parse(file, n = -1, NULL, "?")))

now that leads to calling do_parse in source.c, i.e.
    https://svn.R-project.org/R/trunk/src/main/source.c

which shows you

	if (status != PARSE_OK)
	    errorcall(call, _("syntax error on line %d"), R_ParseError);

The "errorcall(call, ..)" part entails that the message (in an
English locale!) will be

  Error in parse(.....) : syntax error on line <n>

In a German locale, it's e.g.

  Fehler in parse(file, n = -1, NULL, "?") : Syntaxfehler in Zeile 1

--

Hence, for English

       "^Error .* syntax error"
or German
       "^Fehler .* Syntaxfehler"

would work.
I think ideally, one would make use of the things we have
already
	ess-dump-error-re  ( == "[Ee]rror" for English)

and/or better of something derived from

	(defvar ess-R-message-prefixes
	  '("Error:" "Error in"
	    "Warning:" "Warning in"
	    "Warning messages?"))

(which would need to be put in two parts: one for errors the
 other for warnings).

--------

I still think the best solution would be that R (or S-plus or
...) at startup of "inferior-*"
produces these errors on purpose by eval-ing erronous examples
i.e. sends some commands to R such as 

   parse(text="1]")
   eval(parse(text="rpois(-1)"))
   eval(parse(text="rpois(-1,1)"))
   cat("1]", file=(.tf <- tempfile())) ; try(parse(file=.tf)); unlink(.tf)

and out of the R (or S+ ..)
error message  auto-produces the relevant pattern to use.

This way, ESS adapts to the system, including locale setting,
also for future systems / locales.

Martin