setReplaceMethod creates 'object' in the userworkspace

Jonathan Fritzemeier <clausjonathan.fritzemeier at uni-duesseldorf.de>
    on Fri, 23 Jun 2017 16:15:30 +0200 writes:

> Hi,
    > I recognized that the function 'setReplaceMethod' is creating a
    > character vector in the user workspace having the name (e.g. "newClass")
    > of the class used as value. If you can sort out a mistake by myself, I
    > would like you to file a bug report.

Yes, a mistake by yourself (and really not fit for R-devel,
but rather for R-help to which I follow up now)

    > BBFN,
    > Jonathan

setClass("newClass", representation(value="numeric"))

setMethod(f = "initialize", signature = "newClass",
    definition = function(.Object){
        .Object at value <- 1
    return(.Object)
})

setGeneric(name = "myValue",
        def  = function(object) { standardGeneric("myValue") }
)
setGeneric(name = "myValue<-",
        def  = function(object, value) { standardGeneric("myValue<-") }
)

setMethod("myValue", signature(object = "newClass"),
    function(object) {
        return(object at value)
    }
)

setReplaceMethod("myValue", signature = (object = "newClass"),
    function(object, value) {
        object at value <- value
        return(object)
    }
)

Q: what do you think happens with the above [last setReplaceMethod() call] ?
A: it creates an R object named 'object' in the globalenv
   (or the package if this would go into a package)

If just replace  '(object = "newClass")'   by   '"newClass"'
things should be fine.

{{ Removing all the completely redundant return(.), i.e. return
   implicitly rather than via an extra function call would also
   make the code "cleaner" and more R-like  }} 

Best,
Martin

myNewObject <- new("newClass")
print(object)

print(object)

[1] "newClass"