Check the Availability of a Package
assert_package(x, ask = TRUE)needs(x, ask = TRUE)
Invisibly returns NULL.
N. Frerebeau
assert_package() is designed for use inside other functions in your own
package to check for the availability of a suggested package.
If the required packages are not available and R is running interactively, the user will be asked to install the packages.
needs() is an alias for assert_package().
Other validation methods:
assert_constant(),
assert_data,
assert_length(),
assert_lower(),
assert_names(),
assert_numeric,
assert_square(),
assert_type(),
validate()