[R] Automatic traceback

[Prof Brian Ripley]

On Wed, 16 Jan 2008, Michael Hoffman wrote:

> I would like to have an automatic traceback printed on error. Is there
> a way to do this?
>
> options(error=traceback) seems to print the previous error, not the
> current error. I'm guessing this is because the traceback is not set
> until the error handler is done running.

Yes.  .Traceback is written immediately before the jump to toplevel, to 
allow e.g. try() to recover from the problem.

>> options(error=traceback)
>> stop("1")
> Error: 1
> No traceback available
>> stop("2")
> Error: 2
> 1: stop("1")
>> stop("3")
> Error: 3
> 1: stop("2")
>
> I am using R version 2.6.0 (2007-10-03).
>
There is a compact traceback printed automatically in non-interactive use, 
and you can turn that on by the following options

      'showWarnCalls', 'showErrorCalls': a logical. Should warning and
           error messages show a summary of the call stack?  By default
           error calls are shown in non-interactive sessions.


-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
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