I would like to be able to load two versions of a package at once and to do that was thinking of giving each version a different package name in the DESCRIPTION file and the building and installing each such version separately. library(myPkg1) library(myPkg2) and then use myPkg1::myFun() and myPkg2::myFun(). To do that easily it would be convenient if one could change the package name in only one place (the DESCRIPTION file) and have that propagate to all other uses of the package name in the package. Suppose the package were named "myPkg". Then the problem areas are: 1. The NAMESPACE file has myPkg hard-coded like this: useDynLib(myPkg, .registration=TRUE) 2. The configure.ac file has myPkg hard-coded like this: AC_INIT([myPkg], 1.0.0) 3. There are various references to myPkg hard-code throughout the R code, e.g. myPkg::myFun, but I am ok here as I assume this would work where an .onLoad would be used to grab the package name from the .onLoad's pkgname argument: `::`(pkgname, MyFun) (Also some or all of these may not be needed in the first place.) 1. Is there some way to cause these instances to change when the package name in the DESCRIPTION file changes or is there some other approach that would make it easy to change the package name in just one spot or some other way to load two packages that are versions of each other at one time. (The fact that the package has C++ code seems to be the complicating factor.) 2. Are there any examples of CRAN packages that have been set up to make this easy to do? Thanks. -- Statistics & Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.com