R help - Jul 2010 - Recommended way of requiring packages of a certain version?

What is the recommended way of requiring a certain version when loading 
a package (or, indeed, from R itself)?

Perl has the

require module version
use module version
require version
use version

constructs which is kind of what I am looking for (especially 'use' 
which is evaluated at compile time), but R seems to have lost the 
version= argument to require().

The best I have been able to come up with are constructs of the form

if ( utils::compareVersion(utils::packageDescription("data.table", 
fields="Version"), "1.5") < 0 ) stop("Need
data.table version 1.5 or later")
if ( utils::compareVersion(as.character(getRversion()), "2.11") >=
0 )
stop("Does not work yet with latest R.")

But this is tedious and error prone.  I have created my own require() 
function to automate this (it takes a vector of versions and a vector of 
comparisons and only load the package if they are all met), but it is 
non-standard and just that much harder for my colleagues to maintain. 
Somebody must already have done this?

Allan

PS: Shouldn't utils::compareVersion("2.11.0", "2.11")
return zero
instead of one?

Hi Allan,

When you create an R package you can specify in the DESCRIPTION file 
that your package depends on a certain R version and versions of 
packages. For example:

Package: automap
Version: 1.0-7
Date: 2010/05/04
Title: Automatic interpolation package
Author: Paul Hiemstra <p.hiemstra at geo.uu.nl>
Maintainer: Paul Hiemstra <p.hiemstra at geo.uu.nl>
Description: This package performs an automatic interpolation by 
automatically estimating the variogram and then calling gstat.
Depends: R (>= 2.7.0), methods, sp (>= 0.9-4), gstat (>= 0.9-58)
Imports: lattice
License: GPL

So distributing code to other people is preferably done using R 
packages, which gives you this option.

regards,
Paul

On 07/16/2010 09:06 AM, Allan Engelhardt wrote:
> What is the recommended way of requiring a certain version when 
> loading a package (or, indeed, from R itself)?
>
> Perl has the
>
> require module version
> use module version
> require version
> use version
>
> constructs which is kind of what I am looking for (especially 'use'
> which is evaluated at compile time), but R seems to have lost the 
> version= argument to require().
>
> The best I have been able to come up with are constructs of the form
>
> if (
utils::compareVersion(utils::packageDescription("data.table",
> fields="Version"), "1.5") < 0 ) stop("Need
data.table version 1.5 or
> later")
> if ( utils::compareVersion(as.character(getRversion()), "2.11")
>= 0 )
> stop("Does not work yet with latest R.")
>
> But this is tedious and error prone.  I have created my own require() 
> function to automate this (it takes a vector of versions and a vector 
> of comparisons and only load the package if they are all met), but it 
> is non-standard and just that much harder for my colleagues to 
> maintain. Somebody must already have done this?
>
> Allan
>
> PS: Shouldn't utils::compareVersion("2.11.0",
"2.11") return zero
> instead of one?
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide 
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

-- 
Drs. Paul Hiemstra
Department of Physical Geography
Faculty of Geosciences
University of Utrecht
Heidelberglaan 2
P.O. Box 80.115
3508 TC Utrecht
Phone:  +3130 253 5773
http://intamap.geo.uu.nl/~paul
http://nl.linkedin.com/pub/paul-hiemstra/20/30b/770

> So distributing code to other people is preferably done using R packages,
> which gives you this option.
However (as far as I am aware), note that this option is checked at
package build time, not at load time.

Hadley

-- 
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/