[R] Missing link(s) in documentation object

[Martin Morgan]

Jon Olav Skoien wrote:
> Hi,
> 
> I want to cross-reference from the documentation of pkg1 to pkg2, which
> is imported in the NAMESPACE of pkg1, and under Depends in DESCRIPTION
> of pkg1. According to "Writing R extensions", this can be done by:
> \code{\link{foo}}
> when foo is an aliased function in the documentation of pkg2. This works
> as it should when I install the package, but when I run R CMD check
> pgk1, I get a warning:
> 
> * checking Rd cross-references ... WARNING
> Missing link(s) in documentation object 'fooPkg1.Rd'
>  foo
> 
> I have tried to change the link to
> \code{\link[pkg2]{foo}}
> \code{\link[pkg:pkg2]{foo}}

Hi Jon --

I think the current requirement is \link[pkg2;foo_Rd_file_name]{foo}
where foo_Rd_file_name  is the name (without the .Rd extension) of the
FILE in which foo is documented. This would appear not to be foo.Rd,
because you say \link[pkg2]{foo} fails. This is as documented in Writing
R extensions.

> None of these works, the first gives a link that leads to an error page,
> and the second one gives a link that does not work at all. I assume this
> is as it should be; foo.Rd does not exist. However, R CMD check does not
> complain about any of these links...

Try building with R-devel, where the error messages are more detailed.

> Why does R CMD check warn me against links that work? I think pkg2 is

I think the idea is that the cross-package links as you originally
specified work for some help formats, but not for others (e.g., pdf).

Martin

> not on the search path when looking for cross-references, but why? R CMD
> check continues to run after the warning without any complaints, and all
> tests rely on pkg2. I am quite sure there is something simple that I
> have overlooked, but cannot figure out what it is.
> 
> Best wishes,
> Jon
> 
> Platform etc:
> XP SP3, R 2.9-2, Rtools210 (the problem was also there before upgrading
> from R 2.9-1 and Rtools29 )
> 
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.