Dear Seth, > -----Original Message----- > From: Seth Falcon [mailto:s...@userprimary.net] > Sent: September-22-09 5:13 PM > To: Uwe Ligges > Cc: John Fox; r-devel@r-project.org > Subject: Re: [Rd] Rcmdr package dependencies > > * On 2009-09-22 at 20:16 +0200 Uwe Ligges wrote: > > no, this is not possible. > > > > Consider your package A (or Rcmdr) suggests B that suggests C. > > Then A::foo uses the function B::bar which only works if C::dep is > > present. B works essentially without C but it requires C just to > > make bar work. Then this means your A::foo won't work if C is not > > installed and you won't get it with the setup mentioned above. > > > > In summary, I fear what you want might work well *now* (by chance), > > but it does not work in general. > > In general, one would expect a given package to function when its > suggested packages are not available. As such, it seems quite > reasonable to install a package, its Depends, Imports, and Suggests, > but not install Suggests recursively. > > I think you could achieve such an installation using two calls to > install.packages: > > install.packages("Rcmdr") > Rcmdr.Suggests <- strsplit(packageDescription("Rcmdr")$Suggests, > ",\\s?")[[1]] > ## need extra cleanup since packageDescription("blah")$Suggests > ## Returns package names with versions as strings > wantPkgs <- sub("^([^ ]+).*", "\\1", Rcmdr.Suggests) > havePkgs <- installed.packages()[, "Package"] > wantPkgs <- wantPkgs[!(wantPkgs %in% havePkgs)] > install.packages(wantPkgs)
The Rcmdr maintains a list of its dependencies, so it already does something similar to this, but I like your version better because it queries the Description file directly. I can't really expect a user to issue a command like this, so I suppose that the best solution is, as at present, to have the Rcmdr package do the checking and installation at start-up but to install with dep=FALSE. Thanks, John > > + seth > > -- > Seth Falcon | @sfalcon | http://userprimary.net/user ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
