s4

When I tried to use tbl_df in S4 classes, tbl_df slots seems to be transformed into list . library('tibble') setOldClass(c('tbl_df', 'tbl', 'data.frame')) setClass(Class = 'TestClass', slots = c(name = 'character'), contains = 'tbl_df') tmp1 <- new('TestClass', tibble(x = 1:5, y = 1, z = x ^ 2 + y), name = 'firsttest') tmp1@.Data [[1]] [1] 1 2 3 4 5 [[2]] [1] 1 1 1 1 1 [[3]] [1] 2 5 10 17 26 Can I visit the tmp1@.Data just like a tbl_df object? like tmp1@.Data # A tibble: 5 x 3 x y z * <int> <dbl> <dbl> 1 1 1 2 2 2 1 5 3 3 1 10 4 4 1 17 5 5 1 26 S3 objects, just for simplification, are lists

This is related to the following post Problems passing arguments with callNextMethod() in R I am writing accessors for two S4 classes, 'foo' and 'bar'. 'bar' inherits from foo and is extended only by a few slots. Instead of writing a full accessor function for objects of class 'bar' I want to pass the arguments to callNextMethod() when accessing a slot that is inherited by 'foo'. My code looks like this: foo <- setClass("foo", representation(x = "numeric", y = "numeric")) bar <- setClass("bar", representation(distance = "numeric"), contains = "foo") setMethod("[", "bar", function(x, i, j, drop

I ran into following problem already multiple times. Say you have two classes, classA and classB described in the following files classA.R : #' the class classA #' #' This is a class A blabla #' \section{Slots}{\describe{\item{\code{A}}{a Character}}} #' @ name classA #' @rdname classA #' @exportClass classA setClass("classA",representation(A="character")) And classB.R #' the class classB #' #' This is a class B blabla #' \section{Slots}{\describe{\item{\code{B}}{an object of class A}}} #' @ name classB #' @rdname classB #' @exportClass classB setClass("classB",representation(B="classA")) I

I have an R package which currently uses S3 class system, with two different classes and several methods for generic S3 functions like plot , logLik and update (for model formula updating). As my code has become more complex with all the validity checking and if/else structures due to to the fact that there's no inheritance or dispatching based on two arguments in S3 , I have started to think of converting my package to S4 . But then I started to read about the advantages and and disadvantages of S3 versus S4 , and I'm not so sure anymore. I found R-bloggers blog post about efficiency issues

I would like to use a custom reference class inside another reference class, but this code fails: nameClass <- setRefClass("nameClass", fields = list(first = "character", last = "character"), methods = list( initialize = function(char){ chunks <- strsplit(char,"\\.") first <<- chunks[[1]][1] last <<- chunks[[1]][2] }, show = function(){ cat("Special Name Class \n:") cat("First Name:") methods::show(first) cat("Last Name:") methods::show(last) } )) # this works fine nameClass$new("tyler.durden") When I try to add a second class that has a field of class nameClass this class cannot be initiated.

My question: Why is callNextMethod() not passing arguments as expected to the next method? Situation: Say I have two hierarchical classes foo and bar ( bar is subclass of foo ) for which I have a method foobar that can dispatch for both classes (i.e., has methods for both classes). Furthermore, the method for the (sub)class bar calls the method for foo after some calculations with callNextMethod() . Both methods have the same additional argument (with default) that should be passed to the method for foo , where only it is relevant. setClass("foo", representation(x = "numeric")) setClass("bar",