[Rd] wishlist: additional argument in R_tryEval (Rinternals.h)

[Luke Tierney]

Even though it isn't officially part of the API it has seen some use
so I'd prefer not to change the interface; instead add

SEXP R_tryEvalWithVis(SEXP e, SEXP env, int *ErrorOccurred, int *visible);

or something along those lines and define R_tryEval internally in
terms of that.

It may be worth thinking a bit more though to see if there is
something else that might be useful at this point.  I vaguely recall
thinking recently about needing something else of this flavor but I
can't seem to remember what it was exactly -- will try to see if I can
recall.

Best,

luke


On Fri, 6 Apr 2007, Deepayan Sarkar wrote:

> Hi,
>
> R_tryEval, exported in Rinternals.h but not part of the API, is
> currently defined as:
>
> R_tryEval(SEXP e, SEXP env, int *ErrorOccurred);
>
> I'm trying to embed R in an application (basically yet another GUI),
> and this has been very helpful to catch errors. It would be even more
> helpful if it also gave access to the visibility flag. I can wrap this
> in a call to withVisible, and that works great, but if there is an
> error, traceback() contains a bunch of irrelevant levels.
>
> It seems fairly easy to add another argument, similar to
> ErrorOccurred, that is set to the visibility flag before returning. Is
> this something that could be considered for addition in R-devel? A
> possible patch for R/trunk is attached. Mac-GUI/REngine/REngine.m will
> also need a patch, but I don't understand the language it's written
> in.
>
> -Deepayan
>

-- 
Luke Tierney
Chair, Statistics and Actuarial Science
Ralph E. Wareham Professor of Mathematical Sciences
University of Iowa                  Phone:             319-335-3386
Department of Statistics and        Fax:               319-335-3017
    Actuarial Science
241 Schaeffer Hall                  email:      luke at stat.uiowa.edu
Iowa City, IA 52242                 WWW:  http://www.stat.uiowa.edu