Thank you all for your comments, which confirm the feeling I had that 'slot' is only needed in the rare occasions Roger mentioned. Although 'slot' is an accessor function, it seems it's not quite analogous to functions or methods for accessing components of objects.
Cheers, -- Seb ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel