[R] licensing of R packages

[Duncan Murdoch]

On 14/11/2008 4:42 AM, Carlos Ungil wrote:
> I know the standard answer to this kind of question is "get legal
> advice from a lawyer", but I would like to hear the (hopefully
> informed) opinion of other people.
> 
> I would say that, according to the FSF's interpretation of the GPL,
> any R code using GPL packages can be distributed legally only using
> GPL-compatible licenses.

I think they are talking about cases where the GPL libraries are 
compiled into the new product.  Packages generally don't include copies 
of anything from R, so our GPL doesn't apply to them.  (Writers may have 
chosen to copy and modify base functions; if so, they are copying our 
code, and the GPL would apply.)

Duncan Murdoch

> 
> http://www.gnu.org/licenses/gpl-faq.html#IfInterpreterIsGPL
>> Another similar and very common case is to provide libraries with the
>> interpreter which are themselves interpreted. For instance, Perl comes
>> with many Perl modules, and a Java implementation comes with many Java
>> classes. These libraries and the programs that call them are always
>> dynamically linked together.  
>>
>> A consequence is that if you choose to use GPL'd Perl modules or Java
>> classes in your program, you must release the program in a
>> GPL-compatible way, regardless of the license used in the Perl or Java
>> interpreter that the combined Perl or Java program will run on.
> 
> If the reasoning above applies to R as it does to Perl, all R code
> would be affected given that core packages like "base" are GPL.
> 
> The interpretation of the R Foundation (the copyright holder in this
> case) seems more relaxed, but I wonder what is the intent of other
> people distributing R packages under the GPL. Maybe some of them would
> protest if R code using their package was distributed under a
> non-GPL-compatible license. For example, I would expect the authors of
> the GNU Scientific Library to defend that any package using "gsl" (a
> wrapper on their GPL library) should be published under a
> GPL-compatible license, being a derivative work (the FSF thinks so).
> 
> Another question is if that "strict" interpretation of the GPL could
> be actually enforced, of course. Coming back to the GSL example, it
> seems a more flagrant violation of the license is already happening:
> http://www.numerit.com/gsl.htm (apparently the publisher of that
> product thinks that linking to a GPL dll doesn't impose any obligation
> to him, but the usual view of the FSF is quite the opposite; I just
> found that page by chance, I don't know anything else about that
> particular case).
> 
> I've noticed that this question was posed in r-devel a couple of years ago,
> I'm surprised it didn't provoke more than one reply:
> https://stat.ethz.ch/pipermail/r-devel/2006-September/042715.html
> 
> Cheers,
> 
> Carlos
> 
> PS: By the way, I think FAQ 2.11 should be fixed: it states that "R is
> released under the GNU General Public License (GPL)", without
> specifying the version and linking to
> http://www.gnu.org/copyleft/gpl.html (GPLv3). However, the COPYING
> file in the R directory corresponds to GPL2.
> 
>