And if, like me, you always forget which of Depends and Imports is the one you are supposed to be using, the mnemonic device is "DEPends is DEPrecated[1], IMPorts is IMPortant."
Barry [1] kinda. On Thu, Aug 28, 2014 at 4:33 AM, Gavin Simpson <ucfa...@gmail.com> wrote: > On Aug 27, 2014 5:24 PM, "Hadley Wickham" > <snip /> >> I'd say: Depends is a historical artefact from ye old days before >> package namespaces. Apart from depending on a specific version of R, >> you should basically never use depends. (The one exception is, as >> mentioned in R-exts, if you're writing something like latticeExtras >> that doesn't make sense unless lattice is already loaded). > > Keeping this nuance in mind when when discussing Depends vs Imports is > important so as to not suggest that there isn't any reason to use Depends > any longer. > > I am in full agreement that its use should be limited to exceptional > situations, and have modified my packages accordingly. > > Cheers, > > G > >> > This check (whilst having found some things I should have imported and >> > didn't - which is a good thing!) seems to be circumventing the > intention of >> > having something in Depends. Is Depends going to go away? >> >> I don't think it's going to go away anytime soon, but you should >> consider it to be largely deprecated and you should avoid it wherever >> possible. >> >> >> (And really you shouldn't have any packages in depends, they should >> >> all be in imports) >> > >> > I disagree with *any*; having say vegan loaded when one is using > analogue is >> > a design decision as the latter borrows heavily from and builds upon > vegan. >> > In general I have moved packages that didn't need to be in Depends into >> > Imports; in the version I am currently doing final tweaks on before it > goes >> > to CRAN I have remove all but vegan from Depends. >> >> I think that is a reasonable use case for depends. Here's the exact >> text from R-exts: "Field ‘Depends’ should nowadays be used rarely, >> only for packages which are intended to be put on the search path to >> make their facilities available to the end user (and not to the >> package itself): for example it makes sense that a user of package >> latticeExtra would want the functions of package lattice made >> available." >> >> Personally I avoid even this use, requiring users of my packages to be >> explicit about exactly what packages are on the search path. You are >> of course welcome to your own approach, but I think you'll find it >> will become more and more difficult to maintain in time. I recommend >> that you bite the bullet now. >> >> Put another way, packages should be extremely conservative about >> global side effects (and modifying the search path is such a >> side-effect) >> >> Hadley >> >> -- >> http://had.co.nz/ > > [[alternative HTML version deleted]] > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
