similar to: Inheriting from "environment" and similar object types

On Sun, 18 Mar 2018, Jialin Ma wrote: > Dear all, > > I am confused about the inconsistent behaviors of `@<-` operator when > used in different ways. Consider the following example: > > library(inline) > > # Function to generate an externalptr object with random address > new_extptr <- cfunction(c(), ' > SEXP val = PROTECT(ScalarLogical(1)); >

I have a few questions and thoughts regarding class versioning and serialized S4 class instances. How is the version argument to setClass is intended to work? It appears to want an externalptr, but that seems odd to me. setClass("FOO", representation(x="numeric"), version="1.2.3") Error in validObject(.Object) : invalid class

>>>>> Martin Maechler <maechler at stat.math.ethz.ch> >>>>> on Sat, 12 Dec 2015 10:32:51 +0100 writes: >>>>> John Chambers <jmc at r-project.org> >>>>> on Fri, 11 Dec 2015 10:11:05 -0800 writes: >> Somehow, the most obvious fixes are always back-incompatible these days. >> The example intrigued

>>>>> John Chambers <jmc at r-project.org> >>>>> on Fri, 11 Dec 2015 10:11:05 -0800 writes: > Somehow, the most obvious fixes are always back-incompatible these days. > The example intrigued me, so I looked into it a bit (should have been doing something else, but ....) > You're right that this is the proverbial

Or maybe the "right" concept is that "numeric" is a virtual class with 3 subclasses: "complex", "double", and "integer". Anyway it's probably too late for implementing the "right" concept so it doesn't really matter. Thanks Martin for offering to fix the as(1L, "numeric") bug. Very much appreciated. I guess that means

>>>>> "JMC" == John Chambers <jmc at r-project.org> >>>>> on Tue, 28 Oct 2008 11:50:38 -0400 writes: JMC> The asymmetry is just the symptom of a more fundamental JMC> issue: There are no operator methods currently defined JMC> for "vector" classes, either combined with each other JMC> or with a non-S4 object.

On Dec 19, 2015, at 3:32 AM, Martin Maechler <maechler at stat.math.ethz.ch> wrote: >>>>>> Martin Maechler <maechler at stat.math.ethz.ch> >>>>>> on Sat, 12 Dec 2015 10:32:51 +0100 writes: > >>>>>> John Chambers <jmc at r-project.org> >>>>>> on Fri, 11 Dec 2015 10:11:05 -0800 writes: >

As I tried to say on Dec. 11, there are two levels of "fix": 1. The fix to the complaint in the OP's subject heading is to conform to the default third argument, strict=TRUE: as(1L, "numeric") == 1.0 This generates some incompatibilities, as for classes that extend "numeric". But still leaves class(1.0) "numeric" and typeof(1.0) "double".

Hello! as(object,"list") and as(object,"matrix") behave quite differently if it comes to their attributes. I define two classes. One of them "contains" a "list" the other a "matrix" setClass("myclass" ,representation(info="character") ,contains="matrix" ) setClass("mylist"

Hello, Thomas Stabla (statho3@web.de) has already sent this question to R-help, Wed, 12 Nov 2003 21:21:31 +0100, but we are not sure whether we should better post this mail to this audience than to R-help: --------------------------------------------------------------------- We are using S4-classes and want to force a validity check when an object is created. How can this be done, when an

>>>>> Martin Maechler <maechler at stat.math.ethz.ch> >>>>> on Tue, 8 Dec 2015 15:25:21 +0100 writes: >>>>> John Chambers <jmc at r-project.org> >>>>> on Mon, 7 Dec 2015 16:05:59 -0800 writes: >> We do need an explicit method here, I think. >> The issue is that as() uses methods for the generic

Hi, The following question might come from my (deep) misunderstanding of the concepts in the package 'methods'. I have a class 'A', and a class 'B' inheriting 'A' (so defined with 'setClass' and the parameter 'contains="A"'. The class A has a method 'mymethod'. A call to 'showMethods("mymethod")' return the

Hi, In an effort to learn S4 objects, I am trying to port some c based tree code to S4 object. My immediate goal is to use .Call() interface for calling my c code from R. My long term goal is to understand how to write c structs that follows S4 classes and not the other-way-around. The c struct for the node is : typedef struct node{ int c; int n; inode **nodes; //length = n } inode; I

Hi! Consider this code. setClass("Ctest" ,representation( test="character" ,bla="character" ,mod="lm" ) ) new("Ctest",test="bla") #This produces an error. #Error in validObject(.Object) : Invalid "Ctest" object: Invalid object for slot "mod" in class "Ctest": got class

One of the changes some packages are noticing from the recent modifications to methods is warnings of "undefined classes" during installation when the package extends S3 classes or uses them as slots UNLESSS they have been declared in a setOldClass() call. The green book "strongly recommends" declaring S3 classs this way (pp 449-451). The warnings on undeclared classes

When dealing with object holding pointers that are only valid during a single session, it would be convenient to exclude them from being saved with the session image. (I am assuming that `quit` calls `save.image` before quitting or is it internal?) Currently they are saved with the pointer converted to NULL. Its a bit surprising for users not realizing the object is no longer valid. My thought is

Dear all, I am confused about the inconsistent behaviors of `@<-` operator when used in different ways. Consider the following example: library(inline) # Function to generate an externalptr object with random address new_extptr <- cfunction(c(), ' SEXP val = PROTECT(ScalarLogical(1)); SEXP out = PROTECT(R_MakeExternalPtr(&val, R_NilValue, val)); UNPROTECT(2);

I'm trying to create a package for working on orientation data, i.e. data where the observations are 3D rotations. There are several different representations of orientations in common use: SO(3) matrices, Euler angles, unit quaternions, etc. One thing I'd like is to make it convenient to work in any representation, and have conversions to others done as needed. I'm trying to do

Hi, I have a S3 package with namespace called "myS3Pkg". Inside my package I would like to create a S4 class which extends (adds 2 slots) another S4 class from some other package. The class should be created in "myPkg" environment (and not global environment). Using: setClass("myS4class", representation("otherS4class", mydata = "numeric"),

Hi, I don't understand why this code doesn't work (f(b2)): ///////////////// setClass("B0", representation(b0 = "numeric")) setClass("B1", representation("B0", b1 = "character")) setClass("B2", representation("B1", b2 = "logical")) f <- function(x) class(x) setMethod("f", "B0",