Message-ID: <82f987ca-f11d-c6e1-db39-71a8415195e2@yahoo.fr>
Date: 2017-02-02T14:30:57Z
From: Marc Girondot
Subject: Function that works within a package and not when copied in global environment. Why?
Dear experts,
In the package nlWaldTest, there is an hidden function : .smartsub
I can use it, for example:
> getFromNamespace(".smartsub", ns="nlWaldTest")(pat="x", repl="b" ,
x="essai(b[1], b[2], x[1])")
[1] "essai(b[1], b[2], b[1])"
Now I try to create this function in my global environment:
smartsub <- getFromNamespace(".smartsub", ns="nlWaldTest")
It works also:
> smartsub(pat="x", repl="b" , x="essai(b[1], b[2], x[1])")
[1] "essai(b[1], b[2], b[1])"
But if I create the function manually:
> smartsub2 <- function (pat, repl, x)
{
args <- lapply(as.list(match.call())[-1L], eval, parent.frame())
names <- if (is.null(names(args)))
character(length(args))
else names(args)
dovec <- names %in% vectorize.args
do.call("mapply", c(FUN = FUN, args[dovec], MoreArgs =
list(args[!dovec]),
SIMPLIFY = SIMPLIFY, USE.NAMES = USE.NAMES))
}
> smartsub2(pat="x", repl="b" , x="essai(b[1], b[2], x[1])")
Error in names %in% vectorize.args : objet 'vectorize.args' introuvable
It fails because vectorize.args is unknown
Indeed smartsub2 is different from smartsub.
> identical(smartsub, smartsub2)
[1] FALSE
1/ Why are they different? They are just a copy of each other.
2/ Second question, vectorize.args is indeed not defined before to be
used in the function. Why no error is produced in original function?
Thanks a lot
Marc
--
__________________________________________________________
Marc Girondot, Pr
Laboratoire Ecologie, Syst?matique et Evolution
Equipe de Conservation des Populations et des Communaut?s
CNRS, AgroParisTech et Universit? Paris-Sud 11 , UMR 8079
B?timent 362
91405 Orsay Cedex, France
Tel: 33 1 (0)1.69.15.72.30 Fax: 33 1 (0)1.69.15.73.53
e-mail: marc.girondot at u-psud.fr
Web: http://www.ese.u-psud.fr/epc/conservation/Marc.html
Skype: girondot