On Thu, Aug 22, 2013 at 10:05 AM, R. Michael Weylandt <michael.weyla...@gmail.com> <michael.weyla...@gmail.com> wrote: > > > On Aug 22, 2013, at 9:09, Michael Friendly <frien...@yorku.ca> wrote: > >> In checking my vcdExtra package, the following NOTE newly appeared (R-Forge, >> using R version 3.0.1 Patched (2013-08-20 r63635)) >> >> Package in Depends field not imported from: ‘gnm’ >> These packages needs to imported from for the case when >> this namespace is loaded but not attached. >> >> In the DESCRIPTION file, I have >> >> Depends: R (>= 2.10), vcd, gnm (>= 1.0.3) >> >> In NAMESPACE: >> >> # we are a vcd extension >> import(vcd) >> >> I've read 1.1.1 of R-Exts, but it is not clear to me whether I should also >> import gnm or change >> the DESCRIPTION file to use >> >> Imports: vcd, gnm (>= 1.0.3) >> >> R-Exts says: The ‘Imports’ field lists packages whose namespaces are >> imported from (as specified in the >> NAMESPACE file) but which do not need to be attached, but how can I tell if >> gnm needs to be attached? > > I think the current best practice is to use Imports unless gnm provides > functions the end user needs in order to use your package. > > Practically, I think this usually comes down to asking whether gnm provides > relevant generics -- if you provide methods only, the end user would only be > able to call them directly (ick!) unless gnm is both loaded and attached > (Depends) > > If gnm is tools for your code, but not the user to call directly, Imports is > cleaner. > > Does that help? > > Michael > >> >> Also, what is the difference between Imports: in DESCRIPTION and imports() >> in NAMESPACE? >> > > One enables the other: Imports in DESCRIPTION allows for both imports() and > importsFrom(). It could probably be automatic, but the DESC file is much > older than the NAMESPACE file.
I pretty sure you can also use import()/importFrom() in NAMESPACE for packages listed under Depends in DESCRIPTION. /Henrik > > >> -Michael >> >> -- >> Michael Friendly Email: friendly AT yorku DOT ca >> Professor, Psychology Dept. & Chair, Quantitative Methods >> York University Voice: 416 736-2100 x66249 Fax: 416 736-5814 >> 4700 Keele Street Web: http://www.datavis.ca >> Toronto, ONT M3J 1P3 CANADA >> >> ______________________________________________ >> 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 ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
