RStudio.Version() not found on knit

Welcome! Yeah, posting the same thing to multiple categories is frowned upon — but changing categories to get a better fit is encouraged!

For the RStudio IDE vs R Markdown categories, it's tough to know where things go sometimes because R Markdown is so tightly integrated with the IDE. My loose heuristic so far: would this problem apply to somebody who uses R Markdown but doesn't use the RStudio IDE?