similar to: dot dot dot and NextMethod

Hi, although I've done S3 dispatching for more than a decade now, I think I managed to overlook/avoid the following pitfall when using NextMethod(): If you explicitly pass argument '...' to NextMethod(), you will effectively pass those argument twice to the "next" method! EXAMPLE: foo0 <- function(...) UseMethod("foo0"); foo1 <- function(...)

>> One clear moral seems to be don't do anything more inside a >> generic function than you really need to do. Keep it *very* >> simple indeed. >> > I recall JMC saying something like, all generic functions > should be one line long; a call to the appropriate UseMethod. It certainly is encouraging to know that others also have been confused by aspects of

S Programming by Venables and Ripley (page 78) has the example listed at the end of this email. However, I get the following error when I try the example. I don't understand the descriptions of NextMethod on its help page. Could somebody let me know how to fix the error of this example? > test(x) c1 c2 Error in NextMethod() : no method to invoke Calls: test -> test.c1 -> NextMethod

Hi all, I'd like to ask if the following behavior is a bug. To me it certainly feels surprising, at the very least. In this example, I would like to call NextMethod() from my `child` object, have `cols` be left untouched, and then substitute(cols) in the parent method. It works when you use a `parent` object (as expected), but I would have also expected to get `mpg` back when calling it from

My question is when the object argument of NexthMethod be used? In the following example, weather object argument is used will not affects the result. ### foo=function(x) {UseMethod("foo")} foo.cls1=function(x) { x=x+1;class(x)<-"ncls" NextMethod() } foo.ncls=function(x) { cat("ncls\n") } foo.cls2=function(x) { cat("cls2\n");print(x) }

2018-02-22 12:39 GMT+01:00 Tomas Kalibera <tomas.kalibera at gmail.com>: > On 02/22/2018 12:07 PM, I?aki ?car wrote: >> >> 2018-02-22 10:29 GMT+01:00 Tomas Kalibera <tomas.kalibera at gmail.com>: >>> >>> The example is invoking NextMethod via an anonymous function, which is >>> not >>> allowed (see documentation for NextMethod).

The example is invoking NextMethod via an anonymous function, which is not allowed (see documentation for NextMethod). Normally one gets a runtime error "'NextMethod' called from an anonymous function", but not here as the anonymous function is called via do.call. I will fix so that there is a runtime error in this case as well, thanks for uncovering this problem. I

On 02/22/2018 12:07 PM, I?aki ?car wrote: > 2018-02-22 10:29 GMT+01:00 Tomas Kalibera <tomas.kalibera at gmail.com>: >> The example is invoking NextMethod via an anonymous function, which is not >> allowed (see documentation for NextMethod). > Thanks for your response. I definitely missed that bit. > >> Normally one gets a runtime >> error

I've set up a repo with a reproducible example of the issue described in my last email: https://github.com/Enchufa2/dispatchS3dots I?aki 2018-02-20 19:33 GMT+01:00 I?aki ?car <i.ucar86 at gmail.com>: > Hi all, > > Not sure if this belongs to R-devel or R-package-devel. Anyways... > > Suppose we have objects of class c("foo", "bar"), and there are two

Hi all, Not sure if this belongs to R-devel or R-package-devel. Anyways... Suppose we have objects of class c("foo", "bar"), and there are two S3 methods c.foo, c.bar. In c.foo, I'm trying to modify the dots and forward the dispatch using NextMethod without any success. This is what I've tried so far: c.foo <- function(..., recursive=FALSE) { dots <-

I have another problem with NextMethod. Not sure if its related to the last problem. In this example, we have a generic called ff with methods for AsIs and test classes. We call the generic with an object of AsIs class. The corresponding method adds 1 to it and then changes the class to test followed by issuing a NextMethod. However, that results in this error (using R 2.0.0, 2004-10-04

I am encountering difficulty with NextMethod in 0.50-a4. We created a class of groupedData objects which are data.frames with additional attributes. The most important attribute is a formula describing roles of some of the variables in the experimental design. The class of such objects ends in "groupedData", "data.frame". The print method for the groupedData class simply

UseMethod has since the beginning had the 'feature' that local variables in the generic are added to the environment in which the method body is evaluated. This is documented in ?UseMethod and R-lang.texi, but use of this 'feature' has been explicitly discouraged in R-lang.texi for many years. This is an unfortunate design decision for a number of reasons (see below), so the plan

Hello,   ###  I created two classes "A" and "B". "A" is the superclass of "B".   setClass("A", representation(s1="numeric"),prototype=prototype(s1=8)) setClass("B",contains="A",representation(s2="character"),prototype=list(s2="hi")) myA=new("A") myB=new("B")   ####  I created

I have a series of question about methods and generics. The questions are interspersed in some text which explains what I want to do, how it works now and why I do not understand well why it works. Questions are written Q1 and so on up to Q9 and always start a new line. The concrete problem is this: it has become customary after a meta-analysis to quote various statistics to give a picture of the

Full_Name: Mike Kay Version: R-patched OS: Linux Submission from: (NULL) (137.75.70.37) Hi, The following patch cleans up some grammar in the docs for UseMethod (library/base/help/UseMethod) -mike --- UseMethod 2005-09-28 20:06:39.000000000 +0000 +++ /tmp/UseMethod 2005-10-31 21:21:05.534708720 +0000 @@ -5,7 +5,7 @@ Description: R possesses a simple generic function mechanism

I'm a day-old R newbie (but a war-weary S veteran), with couple of first-day questions: In R 0.61, this code fails. Ops.test <- function(e1,e2) { e1 <- NextMethod(.Generic) e1 } x <- 4 class(x) <- "test" y <- x < 3 The error message is "Error in NextMethod(.Generic) : negative length vectors are not allowed.". I assume it is a bug.

Thanks John. ?boxcox says: ************************* Arguments object a formula or fitted model object. Currently only lm and aov objects are handled. ************************* I read that as saying that boxcox(lm(z+1 ~ 1),...) should run without error. But it didn't. And perhaps here's why: BoxCoxLambda <- function(z){ b <- MASS:::boxcox.lm(lm(z+1 ~ 1), lambda = seq(-5, 5,

Hi Bert, On 2023-07-08 3:42 p.m., Bert Gunter wrote: > Caution: This email may have originated from outside the organization. Please exercise additional caution with any links and attachments. > > > Thanks John. > > ?boxcox says: > > ************************* > Arguments > > object > > a formula or fitted model object. Currently only lm and aov objects

I'm running into some hard-to-understand behavior with the evaluation environment when NextMethod is used. I'm using square-bracket indexing into objects, and the evaluation environment of the expression inside the square brackets seems to change depending on what kind of comparison operators are used. This behavior happens when the following conditions are met (this is what I've