R devel - Aug 2012 - Package "datasets" not exporting anything on a recent R-2.15.1-patched

Hi,

I just stumbled on the following apparent oddity: the package
"datasets"
does not appear to export anything out of its namespace:

 > ns_datasets <- getNamespace('datasets')
 > getNamespaceExports(ns_datasets)
character(0)

Not the case with other packages (example here with "utils"):
 > ns_utils <- getNamespace('utils')
 > head(getNamespaceExports(ns_utils))
[1] "?"            ".DollarNames" "adist"       
"alarm" "apropos"
[6] "aregexec"

Is this a temporary glitch, or is there something new and specific to 
"datasets" ?

Best,

Laurent

PS: Obligatory sessionInfo:

 > sessionInfo()
R version 2.15.1 Patched (2012-08-24 r60412)
Platform: x86_64-unknown-linux-gnu (64-bit)

locale:
  [1] LC_CTYPE=en_DK.UTF-8       LC_NUMERIC=C
  [3] LC_TIME=en_DK.UTF-8        LC_COLLATE=en_DK.UTF-8
  [5] LC_MONETARY=en_DK.UTF-8    LC_MESSAGES=en_DK.UTF-8
  [7] LC_PAPER=C                 LC_NAME=C
  [9] LC_ADDRESS=C               LC_TELEPHONE=C
[11] LC_MEASUREMENT=en_DK.UTF-8 LC_IDENTIFICATION=C

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods base

loaded via a namespace (and not attached):
[1] tcltk_2.15.1 tools_2.15.1

On 26 August 2012 at 18:25, Laurent Gautier wrote:
| Hi,
| 
| I just stumbled on the following apparent oddity: the package
"datasets"
| does not appear to export anything out of its namespace:
| 
|  > ns_datasets <- getNamespace('datasets')
|  > getNamespaceExports(ns_datasets)
| character(0)
| 
| Not the case with other packages (example here with "utils"):
|  > ns_utils <- getNamespace('utils')
|  > head(getNamespaceExports(ns_utils))
| [1] "?"            ".DollarNames" "adist"       
"alarm" "apropos"
| [6] "aregexec"
| 
| Is this a temporary glitch, or is there something new and specific to 
| "datasets" ?

Seems to be on purpose -- here is its NAMESPACE file

   # This package exports nothing (it uses lazydata)
   # exportPattern(".")

ie nuttin' gets exported. It also has no R/ directory.

Dirk

-- 
Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

On 26/08/2012 17:25, Laurent Gautier wrote:
> Hi,
>
> I just stumbled on the following apparent oddity: the package
"datasets"
> does not appear to export anything out of its namespace:
>
>  > ns_datasets <- getNamespace('datasets')
>  > getNamespaceExports(ns_datasets)
> character(0)
>
> Not the case with other packages (example here with "utils"):
>  > ns_utils <- getNamespace('utils')
>  > head(getNamespaceExports(ns_utils))
> [1] "?"            ".DollarNames" "adist"    
"alarm" "apropos"
> [6] "aregexec"
>
> Is this a temporary glitch, or is there something new and specific to
> "datasets" ?
Not new, been so since R 2.14.0.

The package contains no R code: the only reason it has a namespace is 
that since 2.14.0 all packages must have one.

There are other data-only packages, but not in base R.

Lazy-loaded data has not been part of the namespace for a long time: 
they are directly in the package's environment.  The reason is the 
namespace scoping rules: if the package's datasets were in its 
namespace, they would be found before any other dataset of that name by 
the package's R functions.

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