drop duplicate code

Author: HenrikBengtsson

R/backend_api-ClusterFutureBackend-class.R

@@ -192,27 +192,3 @@ launchFuture.ClusterFutureBackend <- function(backend, future, ...) {
 
   invisible(future)
 }
-
-
-
-MultisessionFutureBackend <- function(workers = availableCores(), ...) {
-  default_workers <- missing(workers)
-  if (is.function(workers)) workers <- workers()
-  workers <- structure(as.integer(workers), class = class(workers))
-  stop_if_not(length(workers) == 1, is.finite(workers), workers >= 1)
-  
-  ## Fall back to sequential futures if only a single additional R process
-  ## can be spawned off, i.e. then use the current main R process.
-  ## Sequential futures best reflect how multicore futures handle globals.
-  if (workers == 1L && !inherits(workers, "AsIs")) {
-    ## AD HOC: Make sure plan(multicore) also produces a warning, if needed
-    if (default_workers) supportsMulticore(warn = TRUE)
-    ## covr: skip=1
-    return(SequentialFutureBackend(...))
-  }
-
-  core <- ClusterFutureBackend(workers = workers, ...)
-  core[["futureClasses"]] <- c("MultisessionFuture", core[["futureClasses"]])
-  core <- structure(core, class = c("MultisessionFutureBackend", class(core)))
-  core
-}