Re: R-alpha: compatibility

Luke Tierney (luke@stat.umn.edu)
Thu, 30 May 1996 12:23:57 -0500 (CDT)


From: Luke Tierney <luke@stat.umn.edu>
Message-Id: <9605301723.AA04092@nokomis.stat.umn.edu>
Subject: Re: R-alpha: compatibility
To: jlindsey@luc.ac.be (Jim Lindsey)
Date: Thu, 30 May 1996 12:23:57 -0500 (CDT)
In-Reply-To: <9605290833.AA13280@alpha.luc.ac.be> from "Jim Lindsey" at May 29, 96 10:33:55 am

In thinking about compatibility is is probably worth distinguishing
whether you want R always to act like S, which would make life easier
for users who move between the two, or whether you want R to be able
to run S code. Being able to run S code could, in principle be
achieved by constructing a translater that converts S code to R code.
One advantage of this approach woule be that incompatibilities could
at least be flagged. One definite incompatibility is in the
scoping. This is not likely to affect much S code, since local
functions that try to access global data are quite rare, and the
chance of variable capture by an enclosing R function is rarer
still. But it *could* happen (for example in the survival code mike is
porting, which I think does use local functions) and if it does, it is
likely to be a real bear to find the problem.

luke
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
r-testers mailing list -- To (un)subscribe, send
subscribe	or	unsubscribe
(in the "body", not the subject !)  To: r-testers-request@stat.math.ethz.ch
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-