This reads the DESCRIPTION files only, so can only access fields that are
available in the DESCRIPTION file. This is different than installed.packages
which has many other fields, like "Built", "NeedsCompilation" etc. If those
fields are needed, then this function will return an empty column in the returned
character matrix.
Arguments
- lib.loc
character vector describing the location of R library trees to search through, or
NULL
for all known trees (see.libPaths
).- which
a character vector listing the types of dependencies, a subset of
c("Depends", "Imports", "LinkingTo", "Suggests", "Enhances")
. Character string"all"
is shorthand for that vector, character string"most"
for the same vector without"Enhances"
.- other
Can supply other fields; the only benefit here is that a user can specify
"github"
(lower case) and it will automatically add c("GithubRepo", "GithubUsername", "GithubRef", "GithubSHA1", "GithubSubFolder") fields- purge
Logical. Should all caches be purged? Default is
getOption("Require.purge", FALSE)
. There is a lot of internal caching of results throughout theRequire
package. These help with speed and reduce calls to internet sources. However, sometimes these caches must be purged. The cached values are renewed when found to be too old, with the age limit. This maximum age can be set in seconds with the environment variableR_AVAILABLE_PACKAGES_CACHE_CONTROL_MAX_AGE
, or if unset, defaults to 3600 (one hour – seeutils::available.packages
).Internally, there are calls to
available.packages
.- packages
Character vector. If
NULL
(default), then all installed packages are searched for. If a character vector is supplied, then it will only return information about those packages (and is thus faster to execute).- collapse
Logical. If
TRUE
then the dependency fields will be collapsed; ifFALSE
(default) then thewhich
fields will be kept separate.