[Cross-posting to BioC-devel to] Thank you for this.
> The changes are internal but extensive. All packages that use S4 > methods and classes need to be reinstalled from source to use the new > version. Is there an easy way to detect if a package is using S4 or not? If so, I could scan my already installed libraries and call install.packages() on its S4 subset of packages. The alternative is to do install.packages() an all libraries (sic!). Bioconductor: maybe biocLite() could have such an update mechanism built in internally? If I miss to reinstall one S4 package, what should I expect? I assume there will be an error, but I just want to confirm that there is no risk of getting weird "results" but still a running program? Reinstallation is also required for all package that comes as Windows binaries, correct? Best Henrik On 8/30/06, John Chambers <[EMAIL PROTECTED]> wrote: > A revision of r-devel 2.4.0 is being committed today with changes to > method and class management. > > The changes are internal but extensive. All packages that use S4 > methods and classes need to be reinstalled from source to use the new > version. > > The main effects are to speed up method caching and dispatch, and to fix > some problems with selecting inherited methods. The new design is also > cleaner, so we can experiment more easily in the future with changes for > efficiency or semantics. > > The change will mostly be noticeable in attaching packages with many > methods. The CPU time for attaching package Matrix, for example, goes > down by about a factor of 7 compared to R 2.3.1, timed on a Mac G5. > > The other major change is that now _all_ inherited methods are examined > and one of the closest matches is chosen. The old selection took the > first candidate found, so the current version is better defined, and > will also let us experiment with various tuning & strategies. > > There is a draft paper describing method selection at > http://developer.r-project.org/howMethodsWork.pdf > (It's a document in progress, so go back in a few days for a revised > version.) > > If a package uses inheritance for method selection with multiple > arguments, there may well be changes in behavior. We found examples in > both methods itself and in Matrix that needed attention. > > John > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel > > ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
