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rock (version 0.8.1)

checkPkgs: Check for presence of a package

Description

This function efficiently checks for the presence of a package without loading it (unlike library() or require(). This is useful to force yourself to use the package::function syntax for addressing functions; you can make sure required packages are installed, but their namespace won't attach to the search path.

Usage

checkPkgs(
  ...,
  install = FALSE,
  load = FALSE,
  repos = "https://cran.rstudio.com"
)

Value

Invisibly, a vector of the available packages.

Arguments

...

A series of packages. If the packages are named, the names are the package names, and the values are the minimum required package versions (see the second example).

install

Whether to install missing packages from repos.

load

Whether to load packages (which is exactly not the point of this function, but hey, YMMV).

repos

The repository to use if installing packages; default is the RStudio repository.

Examples

Run this code
# \donttest{
rock::checkPkgs('base');

### Require a version
rock::checkPkgs(rock = "0.5.0");

### This will show the error message
tryCatch(
  rock::checkPkgs(
    base = "99",
    stats = "42.5",
    ufs = 20
  ),
  error = print
);
# }

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