[aitap]

Ask tools::Rd2HTML to export the example code in special chunks, parse them and let litedown process them. example(data.table) leaves a new.pdf in the current directory because file.remove("new.pdf") is marked in \dontshow{}, which is, indeed, not shown in the HTML page.

The tables don't look great. We could add some styles (increase margins around each <td>?) or disable HTML tables by overriding litedown:::record_print.data.frame for the duration of the script.

Fixes: #7746

[MichaelChirico]

FWIW I don't see this documented in ?Rd2HTML -- should we add a defensive check here to alert us if some internals change upstream that break our assumption on how to process the result?

The current stopifnot() might suffice... anything more we can assert?

[aitap]

These "rcode" blocks follow the knitr convention for *.Rhtml documents, see the source of the example R HTML vignette. The documentation is at https://yihui.org/knitr/patterns/, but the patterns themselves live in code:

> knitr::all_patterns$html
$chunk.begin
[1] "^\\s*<!--\\s*begin.rcode\\s*(.*)"

$chunk.end
[1] "^\\s*end.rcode\\s*-->"

$ref.chunk
[1] "^\\s*<<(.+)>>\\s*$"

$inline.code
[1] "<!--\\s*rinline(.+?)-->"

$header.begin
[1] "\\s*<head>"

I can adjust our script to use the exact patterns from knitr.

[MichaelChirico]

The tables don't look great.

Any png to share? Or can I preview it somehow?

[aitap]

This is what an HTML table looks without any CSS applied:

<table>
<thead><tr>
<th>x</th>
<th align="right">y</th>
<th align="right">v</th>
</tr></thead>
<tbody>
<tr>
<td>b</td>
<td align="right">1</td>
<td align="right">1</td>
</tr>

To preview, run Rscript site/generate_reference.R and open a file in site/reference/*.html. After running generate_reference.R, it's also possible to run setwd("site"); litedown::fuse_site('.') and navigate to site/manual.html.

[jangorecki]

any reason we use library?
we don't use any dt code, Rd2HTML refers to data.table, stopifnot(requireNamespace()) should be enough

[MichaelChirico]

it seems library() is better regardless for simplicity sake, no?