[Rd] RFC: allow packages to advertise vignettes on Windows

[hadley wickham]

On 5/18/07, Duncan Murdoch <murdoch at stats.uwo.ca> wrote:
> I think we've agreed about adding an option to the vignette() function
> to allow the user to choose to see all vignettes in installed packages,
> or only those that are attached.  Adding this is pretty trivial, and
> I'll put it into R-devel soon.
>
> I'd like to set the default to show only attached packages, which would
> be consistent with the behaviour of demo() and data().  Vignettes are
> still less common than demos or data, so if I do this, I'll also change
> the "none found" message to something like
>
>  > vignette()
> no vignettes found
>
> Use 'vignette(all = TRUE)'
> to list the vignettes in all *available* packages.

What will happen if you do vignette("svmdoc") when you haven't already
loaded the e1071 package?  Will the vignette continue to load (useful)
or return an error message (consistent with help, and data, I think)?
Should data and demo also gain "all" arguments to be consistent?

Hadley