These look like important improvements. As a relative newcomer to the R community, I'm not sure I understand what the procedures are for such changes.
In particular, does the fact that the changes were committed to R-devel mean that the changes have already been reviewed and approved by R Core? Are R Core's discussions / deliberations archived somewhere? What is the role of the larger R community in reviewing and approving changes like this? How is documentation handled? Who is responsible for developing and maintaining a definitive reference manual (not just man pages) which includes all the cumulative changes and describes them comprehensively and in black-box way (not referring to history and implementation details)? Thanks, -s On Sun, Apr 26, 2009 at 3:58 PM, John Chambers <j...@r-project.org> wrote: > Changes were committed today to the r-devel version of R to make S4 and S3 > classes (and abnormal object types such as "environment") work together more > consistently. > > Basically, S4 classes can now contain any S3 class or object type, and > should now inherit S3 methods for these. Also, the main practical problem > with defining S3 methods for other S4 classes (namely, that S4 inheritance > was not recognized) has been fixed, to the extent possible. > > See ?Methods (especially the section on S3 methods). For details (there > are quite a few) see the paper referenced there, > > http://stat.stanford.edu/~jmc4/classInheritance.pdf<http://stat.stanford.edu/%7Ejmc4/classInheritance.pdf> > > Since these changes arguably fix design flaws, I would like to see them in > 2.9.1, so please test them out. For the moment, they are only in the > r-devel version. > > There can be changes to current behavior. For example, I found one > regression test for S4 methods that only worked because an apparent S3 > method, sort.list, was NOT inherited by an S4 class that contained "list". > > John > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel > [[alternative HTML version deleted]] ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel