[R] callNextMethod & initialize & explicit parameters

laurent buffat laurent.buffat at it-omics.com
Mon May 26 18:31:37 CEST 2003


I know that in general, it is better to call callNextMethod without
and so the call is done with the current arguments, but I want explicitly
change the value of
a given argument, how can I do ?

See the code. Why is doesn't work ?

Thanks for your help

Laurent Buffat


setClass("A", representation(a = "numeric"))

setMethod("initialize", "A", function(.Object, a=1, ...)

		   cat("initialize in A\n")
               .Object at a <- a

setClass("B", representation(b = "numeric"),contains=c("A"))

setMethod("initialize", "B", function(.Object, a=1,  b=2, ...)

	      a.init <- b*b # or something more complexe ...
	      .Object <- callNextMethod(.Object,a=a.init, ...)
	      .Object at b <- b

x <-new("B")

/////////////////// error with new("B").
# The evaluation of "a=a.init" is done in the environment of initialize,A,
and a.init doesn't exist
# in this environment ...

initialize in A
Error in .local(.Object, ...) : Object "a.init" not found

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