Various types of R package dependenciesSource:
Various types of R package dependencies
R packages may have various types of dependencies, see Writing R Extensions.pak groups dependencies into three groups:
hard dependencies: "Depends", "Imports", and "LinkingTo",
soft dependencies: "Suggests" and "Enhances",
extra dependencies, see below.
dependenciesargument.You typically use one of these values:
"hard"to install a package and its required dependencies,
TRUEto install all required dependencies, plus optional and development dependencies.
TRUE: This means all hard dependencies plus
Suggestsfor direct installations, and hard dependencies only for dependent packages.
FALSE: no dependencies are installed at all.
NA(any atomic type, so
NA_character_, etc. as well): only hard dependencies are installed.
If a list with two entries named
indirect, it is taken as the requested dependency types, for direct installations and dependent packages.
If a character vector, then it is taken as the dependency types for direct installations, and the hard dependencies are used for the dependent packages.
"hard"is included in the value or a list element, then it is replaced by the hard dependency types. If
"all"is included, then it is replaced by all hard and soft dependency.
pak supports extra dependency types for direct
installations not from CRAN-like repositories.
These are specified with a
Config/Needs/ prefix in the
and they can contain package references, separated by commas.
For example you can specify packages that are only needed for the
pkgdown website of the package:
To use these dependency types, you need to specify them in the
dependencies argument to
Config/Needs/* fields are currently not used from CRAN
packages, and packages in CRAN-like repositories in general.
Usually you specify that a
Config/Needs/* dependency type should be
installed together with
"all", to install all hard or
soft dependencies as well.