Much of this is not a bug. The situation is complex. The options list is dynamic: users can add new options at any time. Options need not be set, and which options are set depends on the platform. Many options if unset have an internal default: this is a protection against a damaged set of options, in particular a broken system Rprofile file. It is an incorrect assumption that setting the previous options returned does re-set the options: it only resets those that were previously set, not those set since. In many cases setting an option to NULL will unset it. There is at least one bug: download.info should not be set, it having been changed to internet.info (which has an internal default).
On Sat, 23 Feb 2002 o.christensen@lancaster.ac.uk wrote:
Dear R-developers There is a discrepancy between the variables found by typing names(options()) and the variables described on the help page for the function ``options''. The following variables are in names(options()) but not described on the help page : "error.messages" "repositories" "show.coef.Pvalues" "help.try.all.packages" "download.info" "dvipscmd"
Some options are documented where they are used: numbers 2 and 4 are, I know. I believe `error.messages' is obselete.
Since options() is part of ``base R'' and the homepage claims that the options described there are the only options used by ``base R'', this may be considered as a bug.
That claim is a bug, not least because ``base R'' is undefined!
The following variables are described on the help page, but are not in names(options()): error show.error.messages download.file.method de.cellwidth internet.info
Right. They can be set if needed, but have internal defaults.
I had a problem with the option ``show.error.messages'' which may be
related to this option not being in names(options()) (I do not claim to
understand how options() really work).
Reporting and checking a problem with ``show.error.messages'' is
actually confusing, since this option changes the printed output from
errors. Here is the problem and my comments on the output (consider
starting a fresh R session).
stop("test - err. mess. printed ")
## prints error mesage, unless ``show.error.messages=FALSE''
op <- options()
options(show.error.messages=FALSE)
stop("test - err. mess. printed ")
## as expected, nothing is printed
options(op)
stop("test - err. mess. printed ")
## Reseting the options, we expect to see the print. Nothing is printed
That does not `reset the options', nor is that what the help page example
says it does (note the word `initial'). The same thing happens with
options("error").
I'll add an explicit default for that one.
Brian D. Ripley, ripley@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 272860 (secr) Oxford OX1 3TG, UK Fax: +44 1865 272595 -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-devel-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._