.installed.pkgs {Require}

Partial alternative (faster) to installed.packages

Description

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.

Usage

.installed.pkgs(
  lib.loc = .libPaths(),
  which = c("Depends", "Imports", "LinkingTo"),
  other = NULL,
  purge = getOption("Require.purge", FALSE),
  packages = NULL,
  collapse = FALSE
)

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 the Require 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 variable R_AVAILABLE_PACKAGES_CACHE_CONTROL_MAX_AGE, or if unset, defaults to 3600 (one hour – see utils::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; if FALSE (default) then the which fields will be kept separate.