Evaluate an R expression with repositories set temporarily

Evaluate an R expression with repositories set temporarily.

withRepos(expr, repos="[[mainstream]]", ..., substitute=TRUE, envir=parent.frame())

Arguments

expr

The R expression to be evaluated.

repos

A character vector of repositories to use.

...

Additional arguments passed to useRepos().

substitute

If TRUE, argument expr is substitute():ed, otherwise not.

envir

The environment in which the expression should be evaluated.

Value

Returns the results of the expression evaluated.

Author

Henrik Bengtsson

See also

Internally, eval() is used to evaluate the expression. See also options() and install.packages.

Examples

if (FALSE) {
  # Install from BioC related repositories only
  withRepos(install.packages("edgeR"), repos="[[BioC]]")

  # Install from CRAN or BioC related repositories only
  withRepos(install.packages("edgeR"), repos=c("CRAN", "[[BioC]]"))

  # Install from mainstream repositories only (same as previous)
  withRepos(install.packages("edgeR"), repos="[[mainstream]]")

  # Install from R-Forge and mainstream repositories only
  withRepos(install.packages("R.utils"), repos="[[R-Forge]]")

  # Update only CRAN packages
  withRepos(update.packages(ask=FALSE), repos="[[CRAN]]")

  # Update only Bioconductor packages
  withRepos(update.packages(ask=FALSE), repos="[[BioC]]")
}