R: Access private functons inside a package

Question

I would like to access private functions inside an R package. I'm sorry if "private" is not exactly the correct word, but hopefully an example can clear up any confusion.

I'm working with the R package hdi (link to CRAN page). In the hdi package, there is a function called multi.split. I can access to function body of multi.split with:

mult.split

or

hdi::multi.split

When I do that, I see that multi.split calls a function called aggregate.ci. I can see that it's in the Namespace of the function:

ls(getNamespace("hdi"), all.names=TRUE)

I want to see the body of the function aggregate.ci, but I have no idea how to do that.