R devel - Jul 2003 - namespace magic

I'm confused about name spaces.  This morning I installed the
boot package because I wanted to look at bca.ci.  So I did
library(boot), but then I had,
> bca.ci
Error: Object "bca.ci" not found

I had a look in the boot R directory and bca.ci was there as expected.
So then I took a look at the NAMESPACE file for the boot package and saw
that bca.ci wasn't exported.  I tried

example(boot.ci)

and this worked fine including computing the bca.ci version of some
intervals.  Finally, I read the section on name spaces in Writing R
extensions, which was very helpful but still didn't answer my basic
question:  how is it that bca.ci is not loaded and still available
to do the example?  And why not export bca.ci and friends?

platform sparc-sun-solaris2.8
arch     sparc
os       solaris2.8
system   sparc, solaris2.8
status   Under development (unstable)
major    1
minor    8.0
year     2003
month    07
day      26
language R

url:	www.econ.uiuc.edu/~roger/my.html	Roger Koenker
email	rkoenker@uiuc.edu			Department of Economics
vox: 	217-333-4558				University of Illinois
fax:   	217-244-6678				Champaign, IL 61820

On Thu, 31 Jul 2003, Roger Koenker wrote:
> I'm confused about name spaces.  This morning I installed the
> boot package because I wanted to look at bca.ci.  So I did
> library(boot), but then I had,
> 
> > bca.ci
> Error: Object "bca.ci" not found
> 
> I had a look in the boot R directory and bca.ci was there as expected.
> So then I took a look at the NAMESPACE file for the boot package and saw
> that bca.ci wasn't exported.  I tried
> 
> example(boot.ci)
> 
> and this worked fine including computing the bca.ci version of some
> intervals.  Finally, I read the section on name spaces in Writing R
> extensions, which was very helpful but still didn't answer my basic
> question:  how is it that bca.ci is not loaded and still available
> to do the example?  And why not export bca.ci and friends?
The answer to the last question is because they are internal functions for 
the boot package.  They are available to functions in the boot package, 
and to functions in any other package with a namespace that imports them.

You can look at non-exported functions by

getFromNamespace("bca.ci", "boot")  # without even
library(boot)
getAnywhere("bca.ci")

and in R-devel

boot:::bca.ci



-- 
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 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595