[Rd] viral setClassUnion?

[Martin Morgan]

I'm looking for help with the following warning message:

Subclass "A" of class "numeric" is not local and cannot be updated for
new inheritance information; consider setClassUnion() in:
.checkSubclasses(class1, classDef, class2, classDef2, where1)

I see this with, e.g.,

R CMD INSTALL --clean

in a package with

DESCRIPTION: SaveImage: yes

and a single R file with

setClass("A", contains="numeric")
setClassUnion("B", members="numeric")
setClassUnion("D", members="character")
setClass("C", contains="character")

The order of setClass / setClassUnion, rather than the contains /
members type, is important; there is no message about C / D.

R version 2.5.0 Under development (unstable) (2006-11-30 r40072) 
x86_64-unknown-linux-gnu 

locale:
LC_CTYPE=en_US;LC_NUMERIC=C;LC_TIME=en_US;LC_COLLATE=en_US;LC_MONETARY=en_US;LC_MESSAGES=en_US;LC_PAPER=en_US;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=en_US;LC_IDENTIFICATION=C

attached base packages:
[1] "stats"     "graphics"  "grDevices" "utils"     "datasets"  "methods"  
[7] "base"     

-- 
Martin T. Morgan
Bioconductor / Computational Biology
http://bioconductor.org