Evaluate R expressions in an attached environment.

attach_eval(
  unquoted_expr,
  name = "local:utils",
  pos = 2L,
  warn.conflicts = TRUE,
  ...,
  expr = substitute(unquoted_expr),
  mask.ok = NULL
)

Arguments

unquoted_expr: The expression to be evaluated, This is automatically quoted.
name: The environment name. If an environment of that name already exists, it is reused, otherwise, a new environment is attached.
pos: The position where to attach the environment, if creating a new one. If an environment of name already exists, pos is ignored.
warn.conflicts: logical. If TRUE (the default), print warnings about objects in the attached environment that that are masking or masked by other objects of the same name.
...: Ignored.
expr: An R language object. This is an escape hatch from the automatic quoting of unquoted_expr.
mask.ok: character vector of names of objects that can mask objects on the search path without signaling a warning if warn.conflicts is TRUE.

Value

The result after evaluating expr, invisibly.

Examples

attach_eval({
  my_helper_funct <- function(x, y) x + y
})

search() # environment "local:utils" is now attached
#>  [1] ".GlobalEnv"        "local:utils"       "package:envir"    
#>  [4] "package:stats"     "package:graphics"  "package:grDevices"
#>  [7] "package:utils"     "package:datasets"  "package:methods"  
#> [10] "Autoloads"         "tools:callr"       "package:base"     
my_helper_funct(1, 1) # the local utility is now available
#> [1] 2

detach(local:utils) # cleanup