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# clone utilities for bit,bit64,ff
# (c) 2014 Jens Oehlschlägel
# Licence: GPL2
# Provided 'as is', use at your own risk
# Created: 2014-03-02
#' Cloning ff and ram objects
#'
#' \command{clone} physically duplicates objects and can additionally change
#' some features, e.g. length.
#'
#' \command{clone} is generic. \command{clone.default} handles ram objects.
#' Further methods are provided in package 'ff'.
#' \command{still.identical} returns TRUE if the two atomic arguments still
#' point to the same memory.
#'
#' @param x \code{x} an R object
#' @param \dots further arguments to the generic
#' @return an object that is a deep copy of x
#' @author Jens Oehlschlägel
#' @seealso \code{clone.ff}, \code{\link{copy_vector}}
#' @keywords IO data
#' @examples
#'
#' x <- 1:12
#' y <- x
#' still.identical(x,y)
#' y[1] <- y[1]
#' still.identical(x,y)
#' y <- clone(x)
#' still.identical(x,y)
#' rm(x,y); gc()
#'
#' @export
clone <- function(x, ...){
UseMethod("clone")
}
#' @describeIn clone default method uses R's C-API 'duplicate()'
#' @export
clone.default <- function(
x
, ... # ignored here
){
.Call(C_R_duplicate, x)
}
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