>>>>> "BDR" == Prof Brian Ripley <[EMAIL PROTECTED]> >>>>> on Mon, 9 Apr 2007 08:24:32 +0100 (BST) writes:
BDR> On Sun, 8 Apr 2007, hadley wickham wrote: >> On 4/8/07, Roger Bivand <[EMAIL PROTECTED]> wrote: >>> On Sun, 8 Apr 2007, Peter Williams wrote: >>>> Hi All, >>>> >>>> I'm new to R from a C and Octave/Matlab background. I >>>> am trying to construct some classes in R to which I >>>> want to attach pieces of data. First, is attr(obj, >>>> 'member name') <- data the accepted way of doing this? >>> No, it isn't. You seem to be trying to deduce new-style >>> classes from a representation used before R 2.4, BDR> (actually, still used) >>> but in any case it would not be sensible. Please consult >>> John M. Chambers. Programming with Data. Springer, New >>> York, 1998, and/or William N. Venables and Brian >>> D. Ripley. S Programming. Springer, New York, 2000, or >>> for a shorter online resource: >>> >>> http://www.stat.auckland.ac.nz/S-Workshop/Gentleman/Methods.pdf >> Unfortunately, all of those references are at least 4 >> years out of date when it comes to S4 methods. Is there >> any comprehensive reference of the current implementation >> of the S4 OO system apart from the source code? ?Methods {i.e. help(Methods)} is not about the *implementation* but still explains quite a bit about the method dispatch part of S4. It has had a URL to for the "How S4 Methods Work" technical report by John Chambers; I've now also added a link to that from http://developer.R-project.org/ (will only be active in ~ a day). Martin BDR> Not that I know of, and it is a moving target. (E.g. I BDR> asked recently about some anomalies in the S4 bit BDR> introduced for 2.4.0 and what the intended semantics BDR> are.) I've said before that I believe we can only help BDR> solve some of the efficiency issues with S4 if we have BDR> a technical manual. BDR> It is unfair to pick out S4 here, but the 'R Internals' BDR> manual is an attempt to document important BDR> implementation details (mainly by studying the code), BDR> and that has only got most of the way through BDR> src/main/*.c. BDR> -- Brian D. Ripley, [EMAIL PROTECTED] Professor of BDR> Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ BDR> University of Oxford, Tel: +44 1865 272861 (self) 1 BDR> South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, BDR> UK Fax: +44 1865 272595 ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.