similar to: Is there a (virtual) class that all R objects inherit from?

Dear list, I was wondering if you could help me out in clarifying something: Is it possible to use class "ANY" in slots/fields of formal classes if you a) do not want to restrict valid classes of that field and b) if you are making explicit use of class inheritance? It seems to work in simple scenarios but produces errors when class inheritance comes into play. So I was

Dear List, when I first started to use S4 classes, I used the function 'completeClassDef()' in order to see the super- and subclasses of a certain class: setClass(Class="A", representation=list(a="numeric")) setClass(Class="B", contains="A", representation=list(b="character")) # Super x <- completeClassDefinition("B")

Dear list, a while ago I posted this at r-devel but got no answers. Hope it?s okay to give it a shot again by cross-posting it here. TIA for any comments, Janko Von: Janko Thyson [mailto:janko.thyson.rstuff at googlemail.com] Gesendet: Montag, 21. Februar 2011 00:58 An: r-devel at r-project. org (r-devel at r-project.org) Betreff: Reference classes: error with missing arguments in method calls

Dear list, is there a way to declare public and private methods in S4 Reference Classes? If not, are there plans to add such a feature? You'll find a small code example of what I mean at Stackoverflow: http://stackoverflow.com/questions/11073253/oop-with-r-is-there-a-way-to-declare-public-and-private-methods-s4-reference-c Thanks a lot, Janko Thyson

Dear list, is it possible that method dispatch checks for superclasses/virtual classes before checking "ANY"? I'd like to build a generic initialization method for all my Reference Class (say "MyDataFrame") objects by having them inherit from class, say "MyRefClassVirtual" (which would have to be a virtual S4 class; there are no virtual Reference Classes,

Dear list, I was wondering how to best implement some sort of a "plugin" paradigm using R methods and the dispatcher: Say we have a function/method ('foo') that does something useful, but that should be open for extension in ONE specific area by OTHERS using my package. Of course they could go ahead and write a whole new 'foo' method including the features they'd

Dear list, I have a reference class which should act as a "generic" superclass for other classes. I've read the respective section at ?setRefClass and put the name of the superclass to the 'contains' argument of an example subclass (see class defs below). Classnames are set in a way that shouldn't result in collation issues (virtual def sourced before superclass def

Dear list, just to make sure that I understand 'unregistering' methods for S4 reference classes correctly: If I registered a method and want to 'unregister' (i.e. remove) this method again, objects/instance created of the respective class still feature the removed method until I do an explicit reassign ('my.instance <- getRefClass("Classname")$new()'), right?

Dear list, I'm a bit puzzled by an ambiguity with respect to the representation of micro-/milliseconds when using 'POSIXlt' objects. It seems that the last digit of the 'sec' attribute sometimes seems to differ from the digits shown when printing the 'POSIXlt' object. You'll find a little SO post with some example code here:

Dear list, I came across a behavior that IMHO is somewhat undesired when calling '$field()': If the field name whose value you're trying to get is *not* a valid field of the Reference Class, then R doesn't stop there with an error, but scans through all enclosing environments/frames. The result is something similar to calling '|get(<objname>, inherits=TRUE)|'

Dear list, I've been trying to get gWidgets/gWidgetsRGtk2 to run every other month for a while, but somehow I simply can't figure out what's going wrong. I tried several distributions of the GTK runtime environment for Windows (http://downloads.sourceforge.net/gladewin32/gtk-2.12.9-win32-1.exe as described in the package's vignette,

Dear list, I'm experimenting with setting up custom 'lib' and 'destdir' directories for my R packages. It seems to me that 'library()' does handle a custom 'lib.loc' argument the way it should for an arbitrary package but NOT for its dependencies on other packages. The latter are looked for in the default lib path (~/R/R-2.x.x/library) and NOT in the custom

Dear List, I'm trying to figure out some best practice way with respect to the naming conventions when building own packages. I'd like to minimize the risk of choosing function names that might interfere with those of other packages (both available ones and those yet to come). I came up with following alternatives 1. Prefixing the actual names (e.g. myPkgfoo() instead of foo()): pretty

Dear list, today I stumbled across the function ?nsl()? for the first time in order to perform a hostname lookup. According to the R Reference Index (Version 2.9.1, page 1522), the function should be part of the "utils" package. However, I cannot find it in the utils package of my installation(s). I've tried the R-versions 2.8.1, 2.9.0 and 2.9.1. I'd be very thankful if

Dear List, I’m doing my first baby steps towards developing own R Packages and ran into the following problem: R CMD check mypackage works fine (no errors, no warnings) R CMD build mypackage works fine (no errors, no warnings) R CMD INSTALL –library=”C:\R\R-2.11.1\library” “something\mypackage\mypackage_1.0.tar.gz” works fine (no errors, no warnings) However, when I try loading the

Dear List, I’m doing my first baby steps towards developing own R Packages and ran into the following problem: R CMD check mypackage works fine (no errors, no warnings) R CMD build mypackage works fine (no errors, no warnings) R CMD INSTALL –library=”C:\R\R-2.11.1\library” “something\mypackage\mypackage_1.0.tar.gz” works fine (no errors, no warnings) However, when I try loading the

Hi Gabriel, and thanks for answering. I'm basically just trying to find a way to use the power of `...` in more complex scenarios and I'm well aware that this might not be the best approach ;-) Regarding your actual question: "Are you suggesting methods be dispatched based on the *contents* of ... [...]?" Yes, I guess currently I kind of do - but not on the argument *names*

Dear List, just out of pure curiosity: is it possible to define a function via 'substitute()' such that the function's formal arguments are specified by a "wildcard" that is substituted when the expression is evaluated? Simple example: x.args <- formals("data.frame") x.body <- expression( out <- myArg + 100, return(out) ) expr <-

Thanks a lot for answering. Before I get into it, please note that everything below bears the big capture "Thanks for trying to help me at all". 1) Yeah, those examples - quite hard to satisfy everyone's needs ;-) While the one side complained that my past examples regarding this issue were not informative enough, others didn't like the more elaborated version (as seems to be

Well, the benefit lies in the ability to pass along arguments via `...` to more than one recipient that use *identical argument names* and/or when these recipients are not necessarily located on the same calling stack layer. I'm *not* after a *general* change in the way arguments are dispatched/functions are called as I'm actually a big friend of keepings things quite explicit (thus