Specifying an Older Package on TRAN
TERR
and
open-source R
search for packages differently. By default, the repository search order for
options('repos')
is set to TRAN, Posit, and then CRAN. If
a package exists in all repositories, then
TERR
selects the version in
TRAN,
but
open-source R
selects the newest one based on the package version number.
About this task
This search-order difference is by design, because if a newer package on CRAN causes problems when tested with TERR, then TRAN contains an older version of a package that has been tested successfully with TERR. (The Posit snapshot contains the version of the package available when this version of TERR was made available.)
In some cases, you must use open-source R to install a package to use with TERR. For example, under Linux, packages with source code for use in TERR often need to be installed using open-source R. If you encounter the search-difference issue with such a package, and an older version is available on TRAN, then you must take additional steps to make sure you get the working package version.