[Rd] packages with Sweave and knitr vignettes?

[Michael Friendly]

Now that R 3.0.0+ supports non-Sweave vignettes, R-exts \S 1.4.2 seems 
to imply that
it is possible to include both Sweave and knitr vignettes in a single 
package.

I'm wondering
if anyone has tried this and/or if there are some hidden gotchas putting 
this into practice,
and concerned about creating problems with CRAN checks if I try this.

Consider two vignettes:

pkg/vignettes/vign1.Rnw, containing:
% !Rnw weave = Sweave
%\VignetteEngine{Sweave}
...

pkg/vignettes/vign2.Rnw, containing:
% !Rnw weave = knitr
%\VignetteEngine{knitr::knitr}
...

both are .Rnw files, distinguished only by \VignetteEngine. vign1.Rnw is 
currently in my
package, and vign2.Rnw compiles OK outside it, using knitr in an R 
console or RStudio.

R-exts implies that the DESCRIPTION file must include (minimally):

VignetteBuilder: Sweave, knitr
Suggests: knitr

Is anything more/different required?  Does a package exist that does this?

TIA
-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
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