Hi Sven -- Sven Laur wrote: > First, if I have an S4 class boo should I define S3 method for printing > print.boo(..) or should I define S4 method print(..). > I mainly need to define print function only because some user might call > it and then I would like to dispatch the call to > right function instead.
Usually one would define a 'show' method on S4 objects; no need for print.boo setMethod(show, "boo", function(object) cat("Boo!\n")) The user gets to the right place even with print(new('boo')). Can't help with the rest of your post. Martin > > Second, it seems that by defining S4 generic function print, it is > possible to break argument hinting on the status bar. > Namely, as I understand, the Mac OS X GUI client makes a call args() if > something like > > letter( > > is typed to console. Since letter() function does not exists, it should > return nothing to the status bar and nothing to > console, as I as a user have not entered any call, yet. However, if S4 > generic print is defined, a mysterious error > message > > Error in args(letter) : no function to return from, jumping to top level > > appears after typing > > letter() > > without return('\n') to console. It seems bizarre... > > System is > > Mac OS X 10.5.8 (PowerPC) > R 2.9.1 GUI 1.28 Tiger build 32-bit (5444) > R version 2.9.1 (2009-06-26) > > Minimal amount of code to get the behaviour is > > if(!isGeneric("print")) {setGeneric("print",useAsDefault=print)} > > What is the underlying problem? > > Sven Laur > > ______________________________________________ > R-help@r-project.org 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. -- Martin Morgan Computational Biology / Fred Hutchinson Cancer Research Center 1100 Fairview Ave. N. PO Box 19024 Seattle, WA 98109 Location: Arnold Building M1 B861 Phone: (206) 667-2793 ______________________________________________ R-help@r-project.org 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.