[Rd] SweaveParseOptions, quoted commas, and knitr vignettes

[Ben Bolker]

Yihui Xie <xie <at> yihui.name> writes:

> 
  [snip]

  thanks, that all makes sense.

> Two approaches to solve the problem:
> 
> 1. either you Depends on knitr,
> 2. or make install.packages() also install VignetteBuilder (specified
> in DESCRIPTION) when the user chooses to install from source, i.e.
> install.packages(..., type = 'source')
> 
  [snip]

> Or if you want a less cryptic error message, put a code chunk like
> this in your Rnw document:
> 
> <<setup, include=FALSE>>=
> library(knitr)
>  <at> 
> 
> I think R will emit an error that knitr was not installed, which can
> be more helpful for the users to realize the real problem.

  I like the third option here. It might be nice if this were documented
in the "Writing R extensions" manual, although I guess I shouldn't complain
until I volunteer to write a documentation patch ...

  Ben