[Rd] \link{\url{anything}} gives Rdconv trouble (PR#6496)

[d.firth at warwick.ac.uk]

Full_Name: David Firth
Version: 1.8.0
OS: Mac OS 10.2.8
Submission from: (NULL) (80.177.12.48)


In .Rd files, we use \url{stuff} to refer to a URL on the web.  Just as the
documentation says.

Perhaps this isn't a bug, then, but certainly it's a trap for the unwary.  If
the construction
   \link{url{something}}
appears in a .Rd file, then 
   Rdconv --type=html ...
gets stuck and appears to grow and grow and grow...

My version of Perl is 5.6.0.

A warning in the documentation might be considered a fix for this, although it
might reasonably be regarded as going too far in warning people against their
own stupidity!  

Would it be better if it caused an error?  I have no idea what would be involved
in trapping that, and obviously if it's not a simple matter then this is one for
the trashcan.

David