10.4 Attaching versus loading
If a package is installed,
- Loading makes a package available in memory, but not added to the search path
- Attaching put package in the search path
Technically, library() loads then attach the package.
Four functions make a package available:
| Throws error | Returns FALSE |
|
|---|---|---|
| Load | loadNamespace("x") |
requireNamespace("x", quietly = TRUE) |
| Attach | library(x) |
require(x, quietly = TRUE) |
library()great for data analysis or vignette- Use
requireNamespace("x", quietly = TRUE)to specify different behavior based on a package being installed - Other two unlikely to be needed in generic situations