R/lapply.R

In robertzk/monadicbase: The R Base Package

#  File src/library/base/R/lapply.R
#  Part of the R package, https://www.R-project.org
#
#  Copyright (C) 1995-2012 The R Core Team
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  A copy of the GNU General Public License is available at
#  https://www.R-project.org/Licenses/

lapply <- function (X, FUN, ...)
{
    FUN <- match.fun(FUN)
    ## internal code handles all vector types, including expressions
    ## However, it would be OK to have attributes which is.vector
    ## disallows.
    if(!is.vector(X) || is.object(X)) X <- as.list(X)
    ## Note ... is not passed down.  Rather the internal code
    ## evaluates FUN(X[i], ...) in the frame of this function
    .Internal(lapply(X, FUN))
}

rapply <-
    function(object, f, classes = "ANY", deflt = NULL,
             how = c("unlist", "replace", "list"), ...)
{
    if(typeof(object) != "list")
        stop("'object' must be a list")
    how <- match.arg(how)
    res <- .Internal(rapply(object, f, classes, deflt, how))
    if(how == "unlist") unlist(res, recursive = TRUE) else res
}