Can Rcpp package DLLs be unloaded without restarting R?

Question

When installing a Rcpp package on Windows, you need to ensure that the package DLL is unloaded or you get a "Permission Denied" error when copying the new DLL. This means restarting R on every recompile, which is pretty annoying. Is there any way to unload the package DLL without killing R?

I've tried the detach("package:my_package", force=TRUE) command, but it doesnt unload the DLL.

Answer 1

Opinions are divided on this. I often prefer to run the builds and test outside of my main R session(s), simply by chaining R CMD INSTALL with Rscript (or, on Linux, r calls from littler) to test the new build. If you use proper options to R CMD INSTALL ... to skip parts that may take extra time you get a quick turnaround AND are assured that you do get a fresh build.

And if you want the same behaviour by clicking a button, RStudio offers it too.