package: A (possibly) very silent and multi-package...
In svMisc: 'SciViews' - Miscellaneous Functions

Description Usage Arguments Value Note See Also Examples

This function loads one or several R packages as silently as possible (with warn/message = FALSE) and it returns TRUE only if all packages are loaded successfully. If at least one loading fails, a short message is printed, by default. For all packages that were not found, an entry is recorded in .packages_to_install in SciViews:TempEnv, and that list can be automatically used by Install().

package(
  ...,
  stop = TRUE,
  message = stop,
  warn.conflicts = message,
  pos = 2L,
  lib.loc = NULL,
  verbose = getOption("verbose")
)

`...`	The name of one or several R packages to load (character strings).
`stop`	If `TRUE`, issue an error in case the package(s) cannot be loaded.
`message`	Do we display introductory message of the package? If a package displays such a message, there is often a good reason. So, it is not a good idea to disable it in interactive sessions. However, in other contexts, like in non-interactive use, inside an R Markdown document, etc., it is more convenient not to display it.
`warn.conflicts`	As for `library()`: "logical. If TRUE, warnings are printed about conflicts from attaching the new package. A conflict is a function masking a function, or a non-function masking a non-function.
`pos`	As for `library()`: "the position on the search list at which to attach the loaded namespace. Can also be the name of a position on the current search list as given by `search()`". Only one position can be provided here, even if several packages, and they will be all inserted one after the other at the given position.
`lib.loc`	As for `library()`: "a character vector describing the location of R library trees to search through, or `NULL`. The default value of `NULL` corresponds to all libraries currently known to `.libPaths()`. Non-existent library trees are silently ignored".
`verbose`	A logical indicating if additional diagnostic messages are printed.

TRUE if all packages are loaded correctly, FALSE otherwise, with a details attribute indicating which package was loaded or not.

This function is designed to concisely and possibly quietly (with warn = FALSE) load packages and attach them to the search path. Also, on the contrary to library(), or require(), it is not possible to use unquoted names of the packages. This is cleaner, and avoids the contrived work-around to pass name(s) of packages as a variable with an arguments character.only = TRUE!

If several packages are provided, they are loaded and attached in reverse order, so that the order in the search path is the same one as the order in the provided vector.

The library(help = ...) version is not implemented here.

require(), library(), Install()

# This should work...
if (package('tools', 'methods', stop = FALSE)) message("Fine!")
# ... but this not (note that there are no details here!)
if (!package('tools', 'badname', stop = FALSE)) message("Not fine!")
## Not run: 
# Get an error
package('badname')

## End(Not run)