From andy_liaw@merck.com  Mon Feb  3 20:53:35 2003
From: andy_liaw@merck.com (Liaw, Andy)
Date: Mon Feb  3 20:53:35 2003
Subject: [Rd] RE: [R] Bus error with xyplot
Message-ID: <3A822319EB35174CA3714066D590DCD534BC2C@usrymx25.merck.com>

> From: ripley@stats.ox.ac.uk [mailto:ripley@stats.ox.ac.uk]
> 
> On Mon, 3 Feb 2003, Liaw, Andy wrote:
> 
> > > From: Martin Maechler [mailto:maechler@stat.math.ethz.ch]
> > > 
> > > >>>>> "Giovanni" == Giovanni Petris <GPetris@uark.edu>
> > > >>>>>     on Mon, 3 Feb 2003 08:36:06 -0600 (CST) writes:
> > > 
> > >     Giovanni> Has anybody else experienced something like the 
> > > example below? 
> > > not recently.
> > > Could it be that your version of the `grid' package (which is
> > > loaded by `lattice') or `lattice' are incompatible (i.e. older
> > > than) to your R version?
> > > After   library(lattice), use 
> > >  .path.package()
> > > to see where it was loaded from.
> > 
> > This brings up (IIRC) a topic that was discussed on R-devel 
> a while ago:
> > Version checks for required packages.  Is this feasible?  
> Seems quite
> > worthwhile to me...
> 
> It's not feasible.  If package A is upgraded and makes 
> package B need an 
> upgrade, there is no way for package B's maintainer to 
> anticipate this.
> Now one could be conservative and have B require exactly one 
> version of A,
> but then upgrading A makes B unusable.  (The latter is what 
> has happened a 
> few times with ghostscript and gsview/windvi.)

Well, I was thinking of only one-way: much like the package requiring R
version >= something, also allow requiring package blah version >=
something.  Of course, if a new version of package blah has API changes that
breaks the package requiring it, then the maintainer should pay close
attention to the package that he/she is requiring so as to minimize this
from happening...
 
> I have suggested before that grid be more closely integrated 
> with R, and 
> become a base package.  Then grid would only be changed when 
> the R version 
> changes, and the critical incompatibility goes away.

Or, I guess, another possibilities is to have lattice/grid become conjoint
twins; i.e., make them into a package bundle.

Andy

> 
> Brian
> 
> -- 
> Brian D. Ripley,                  ripley@stats.ox.ac.uk
> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> University of Oxford,             Tel:  +44 1865 272861 (self)
> 1 South Parks Road,                     +44 1865 272866 (PA)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595
> 
> 

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[Rd] RE: [R] Bus error with xyplot
Liaw, Andy