dependencies - How to tell what packages you have used in R

Question

I have a very long R script with many if statements and exception cases. As i've been going, if been importing and testing libraries as I've gone and haven't really documented them very well. The problem is that if I run this from a clean installation, i'm not sure which statements the script will run, and so which libraries will be needed.

My question is: Is there any R function to test which libraries are being used in a script?

EDIT: I have not used all of the libraries that have been installed so print(sessionInfo()) won't be useful but and I just want to start the script with an install.packages function

Answer 1

I found the list.functions.in.file() function from NCmisc (install.packages("NCmisc")) quite helpful for this:

list.functions.in.file(filename, alphabetic = TRUE)

For more info see this link: https://rdrr.io/cran/NCmisc/man/list.functions.in.file.html