[Rd] UTF-8 characters in Rd files

[Gábor Csárdi]

Dear list,

I am trying to see if there is a way to expand the set of UTF-8
characters that we can use in Rd files. The main blocker is LaTeX when
building the PDF manual.

It is possible to use the inputenx LaTeX package, instead of inputenc,
which is an improvement, by setting the RD2PDF_INPUTENC env var before
running R CMD Rd2pdf. However, I don't see a way to make this
automatic for a package, so we cannot use it for CRAN packages, as far
as I can tell.

Am I missing something? Would it make sense to have a way to specify
RD2PDF_INPUTENC (and possibly other similar env vars) for packages?

As for the possible implementation, one way would be to have a file
called `environ` or something similar in /man, that could define env
vars, and Rd2pdf would just read it in with readRenviron().

Thanks,
Gabor