200update.txt

Updating packages for 2.0.0
===========================

Package maintainers should be aware of the following changes scheduled
to appear in 2.0.0.


1) Package R code should only create R objects via assignments
   (possibly conditionally or via load()), and not execute functions
   with side effects such as data(), require() and options() -- the
   latter should be in .First.lib or .onLoad (the latter for packages
   with namespaces).

   This is necessary to allow the `lazy loading' of R objects.


2) data/*.R files must be self-sufficient, and in particular not
   depend on the package or standard packages other than base.  (This
   has always been documented, but is now enforced.)  If necessary,
   include a call like

       require(foo, quietly = TRUE, save = FALSE)

   in the .R file or if your package has a namespace, use calls like
   stats::ts.


3) When a package is installed, all the data sets are loaded to see
   what they produce.  If this is undesirable (because they are
   enormous, or depend on other packages that need to be installed
   later, ...), add a `datalist' file to the data subdirectory as
   described in `Writing R Extensions' (in R 2.0.0).


4) If your package uses an empty install.R just to force the save of
   an image, consider replacing it by either

       SaveImage: yes

   or

       LazyLoad: yes

   fields in your DESCRIPTION file, preferably the latter except for
   small packages.


5) Packages named in the Depends: field will be loaded first.  So
   please check the difference between Depends: and Suggests: in
   `writing R Extensions'.  You can probably remove all calls to
   require() in R_PROFILE.R, install.R and .First.lib/.onLoad by
   proper use of the Depends: field.


6) The description of the Depends: field in the DESCRIPTION file has
   been clarified, and a new Imports: field added.  Please check your
   usage against `Writing R Extensions'.


7) Packages whose data directory cannot be zipped should add 
   `ZipData: no' to the DESCRIPTION file.  Examples include anm, 
   mlbench, pls.pcr, RadioSonde and tapiR.


8) Packages which access files via stdio.h and which might conceivably
   be used for files of > 2Gb on 32-bit platforms should consider
   making the transitional large file support available.  This needs a
   configure test for off_t, fseeko and ftello (which should be used
   in place of fseek and ftell) plus some way for the user to indicate
   the suitable C flags (probably -D_FILE_OFFSET_BITS=64
   -D_LARGEFILE_SOURCE=1).


9) Please do NOT install a copy of the (L)GPL COPYING[.LIB] files, but
   refer to the ones in the R distribution (which are always
   installed).  So if you have a file COPYING in the top-level
   directory of your package it might be something like

Licence
=======

    This is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.


The file COPYING in the R top-level directory is a copy of the 'GNU
General Public License'.

[The place might chgange prior to release.]