R help - Jan 2013 - help with knit_hooks

Dear R-listers,

does anybody can suggest some manual where I can learn more about how the
hooks in knitr work?

I am trying to enclose the output of an R command in the Latex verbatim
environment.
I defined a hook as follows:

knit_hooks$set(fsverb = function(x, options) {
  paste("\\begin(verbatim)\n", x, "\\end(verbatim)\n", sep =
"")
}

then I set a chunk as follows:

<<expl-emp, echo = TRUE, results = 'asis', fsverb =
TRUE>>names(data)
@

but when I compile, I get a message of error saying that the compiler (in R
studio) is quitting from lines ...

I know that this is my fault because I don't know how to properly use the
hooks, therefore I am asking if anybody can advice a reference where I can
understand how the hooks and their options work and  how to set them.

Thanks in advance for your kind help,
f.



-- 
Francesco Sarracino, Ph.D.
https://sites.google.com/site/fsarracino/

	[[alternative HTML version deleted]]

This is the only public reference at the moment:
http://yihui.name/knitr/hooks (which has explained why your hook does
not work)

Or learn by examples: https://github.com/yihui/knitr-examples (e.g. example 045)

Or in the spirit of "Luke, use the source!", see
https://github.com/yihui/knitr

Regards,
Yihui
--
Yihui Xie <xieyihui at gmail.com>
Phone: 515-294-2465 Web: http://yihui.name
Department of Statistics, Iowa State University
2215 Snedecor Hall, Ames, IA


On Thu, Jan 10, 2013 at 6:51 AM, Francesco Sarracino
<f.sarracino at gmail.com> wrote:
> Dear R-listers,
>
> does anybody can suggest some manual where I can learn more about how the
> hooks in knitr work?
>
> I am trying to enclose the output of an R command in the Latex verbatim
> environment.
> I defined a hook as follows:
>
> knit_hooks$set(fsverb = function(x, options) {
>   paste("\\begin(verbatim)\n", x, "\\end(verbatim)\n",
sep = "")
> }
>
> then I set a chunk as follows:
>
> <<expl-emp, echo = TRUE, results = 'asis', fsverb =
TRUE>>> names(data)
> @
>
> but when I compile, I get a message of error saying that the compiler (in R
> studio) is quitting from lines ...
>
> I know that this is my fault because I don't know how to properly use
the
> hooks, therefore I am asking if anybody can advice a reference where I can
> understand how the hooks and their options work and  how to set them.
>
> Thanks in advance for your kind help,
> f.
>
>
>
> --
> Francesco Sarracino, Ph.D.
> https://sites.google.com/site/fsarracino/