library() function fails to load multiple packages

Question

When I included janitor package with other packages, it did not load.

library(MASS, caret, stepPlr, janitor)

Error in library(MASS, caret, stepPlr, janitor) : object 'janitor' not found

When I ran that command separately with only janitor package, it got loaded into session; with no error

> library(janitor)
Warning message:
package ‘janitor’ was built under R version 3.3.3 

Is there any limit with including x number of packages at a time? Or there is something wrong with my RStudio?

Answer 1

The function p_load from the pacman package allows for listing multiple packages like this, and will install them if any are not already present:

library(pacman)
p_load(MASS, caret, stepPlr, janitor)

This is not only user-friendly, it also improves reproducibility for running the same script across multiple users or environments.