[R-pkg-devel] "Progress reports" for examples in packages.

Many thanks to Henrik Bengtsson and Martin Maechler for pointing out
that I can monitor progress by looking at the file

     "mypkg.Rcheck/mypkg-Ex.Rout"

e.g. by using "tail -f".  This strategy indeed revealed where the hangup
was happening.  I wrapped a line of the examples in \dontrun{} and
checked the package again.  Now the checking completes in finite time! :-)

However I remain puzzled as to *why* the line in question induces a
hangup.  When I load the package and run that same  line from the
command line, a result is returned within about 5 seconds of "wall time"
(or less).

Another strangeness:  The line prior to that which I wrapped in
\dontrun{} took a very long time to return a result, although the
command did eventually complete (after which everything ran swiftly).
But when I run this same line from the command line it completes
*instantaneously*.

Why on earth would commands be slow, or not execute at all, when run
under the aegis of "R CMD check", but execute swiftly from the command line?

I think it would be unwise of me to ignore the fact that something
strange is going on here, but I'm damned if I can see how to go about
tracking the strangeness down so as to be able to remedy it.

My usual practice when trying to get a handle on something that I don't
understand is to insert browsers() into the code at strategic points.
See fortunes::fortune(158).  That's of no help in the current context in
which the problem only arises when R CMD check is being run.

Can anyone suggest a clever means by which I might determine the
"magnitude and direction of my stupidity"?

cheers,

Rolf

--
Honorary Research Fellow
Department of Statistics
University of Auckland
Phone: +64-9-373-7599 ext. 88276