How to pass command-line arguments when calling source() on an R file within another R file

Question

In one R file, I plan to source another R file that supports reading two command-line arguments. This sounds like a trivial task but I couldn't find a solution online. Any help is appreciated.

Answer 1

I assume the sourced script accesses the command line arguments with commandArgs? If so, you can override commandArgs in the parent script to return what you want when it is called in the script you're sourcing. To see how this would work:

file_to_source.R

print(commandArgs())

main_script.R

commandArgs <- function(...) 1:3
source('file_to_source.R')

outputs [1] 1 2 3

If your main script doesn't take any command line arguments itself, you could also just supply the arguments to this script instead.