evaluate an R6 object within its enclosed environment

enclose.R

#' Evaluate an R6 object within its enclosed environment
#'
#' @param x An R6 object
#' @param expr An expression to run
#' @export
#' @examples
#' Foo <- R6::R6Class(
#'   "Foo", 
#'   public = list(
#'     hello = function() cat("hello\n")
#'   ),
#'   private = list(
#'     goodbye = function() cat("bye\n")
#'   )
#' )
#' foo <- Foo$new()
#' foo$hello()
#' try(foo$private$goodbye())
#' enclose(foo, private$goodbye())
enclose <- function(x, expr) {
  stopifnot(inherits(x, "R6"))
  eval(substitute(expr), get(".__enclos_env__", x))
}