# [Rd] Warning: missing text for item ... in \describe?

Berwin A Turlach berwin at maths.uwa.edu.au
Sat Dec 6 06:13:50 CET 2008

G'day Brian,

On Fri, 5 Dec 2008 17:32:58 +0000 (GMT)
Prof Brian Ripley <ripley at stats.ox.ac.uk> wrote:

[...]
> > Which platform are we talking here?  I was using linux and "R CMD
> > check fda", using R 2.8.0, on the command line said:
>
> That writes to a file, and writes to a file are buffered.  Try R CMD
> INSTALL, where they are not.  We do recommend getting a clean install
> before R CMD check.

Indeed, forgot about that.  Thanks for reminding me.  With R CMD
INSTALL the messages are right next to the help files with the problems.

> >> This *is* an error: nothing in the description allows whitespace
> >> between arguments to \item (nor \section). It seems that only a few
> >> people misread the documentation (sometimes even after their error
> >> is pointed out to them).
> >
> > But there is also nothing that explicitly forbid such whitespace, is
> > it?  I guess this comes down to the question whether "everything is
> > allowed that is not expressively forbidden" or "everything is
> > forbidden unless it is expressively allowed".  Strangely enough,
> > though I am German, I don't tend to subscribe to the latter
> > philosophy.
>
> It really doesn't matter: the author of the convertor (not me)
> decidedly to silently ignore arguments after whitespace so you get an
> incorrect conversion. I also added sentences to the documentation
> that say that explicitly.  But if I see documentation that says
>
> \item{foo}{bar}
>
> I don't see why anyone would be surprised that
>
> \item {foo} {bar}
>
> goes haywire.

Well, I was. :)  And I guess anybody who knows that the TeX parser does
not care about whitespaces between arguments to macros but forgets
that .Rd files are not directly parsed by the TeX parser would have
been surprised too.

Use of whitespace and indentation is pretty much a matter of taste and
personal style to improve readability; and while there are languages
where they matter (Python, makefiles, &c), and some projects (including
R) have style-guides, usually a developer is left with a lot of
flexibility to suit her or his style.  But I guess only Spencer knows
why a whitespace at this place was desirable and/or improved

Cheers,

Berwin