Ensure an object is a dockerfile

Verifies that the provided object is a valid dockerfile class object, throwing an error if not. Useful for validation inside functions that expect dockerfile objects.

Usage

check_dockerfile(dockerfile)

Arguments

dockerfile

Object to check

Value

Invisibly returns TRUE if valid, otherwise throws an error

See also

is_dockerfile() for checking if an object is a dockerfile & dockerfile() for creating a dockerfile object

Other dockerfile core functions: add_dockerfile_line(), dockerfile(), is_dockerfile(), print.dockerfile()

Examples

df <- dockerfile()
check_dockerfile(df)
if (FALSE) { # \dontrun{
# This would throw an error
check_dockerfile(list())
} # }