Retain Objects in an Environment

retain removes all objects from the environment except those mentioned as argument.

Usage

retain(..., list = character(0), envir = parent.frame(),force=FALSE)

Arguments

...: names of objects to be retained, as names (unquoted) or character strings(quoted).
list: a character vector naming the objects to be retained.
envir: the environment from which the objects are removed that are not to be retained.
force: logical value. As a measure of caution, this function removes objects only from local environments, unless force equals TRUE. In that case, retain can also be used to clear the global environment, the user's workspace.

Examples

local({
  foreach(x=c(a,b,c,d,e,f,g,h),x<-1)
  cat("Objects before call to 'retain':\n")
  print(ls())
  retain(a)
  cat("Objects after call to 'retain':\n")
  print(ls())
})
#> Objects before call to 'retain':
#> [1] "a" "b" "c" "d" "e" "f" "g" "h"
#> Objects after call to 'retain':
#> [1] "a"
x <- 1
y <- 2
retain(x)