Re: [PATCH 09/19] gnu: Add r-markdown.

[Ricardo Wurmus <ricardo.wurmus@mdc-berlin.de>]

> From 7e291c7f87498368be556941f6eb7315f94a7c74 Mon Sep 17 00:00:00 2001
> From: Vicente Vera Parra <vicentemvp@gmail.com>
> Date: Sun, 13 Sep 2015 13:17:39 -0300
> Subject: [PATCH 09/19] gnu: Add r-markdown.

> * gnu/packages/statistics.scm (r-markdown): New variable.

[...]

> +    ;; Skip check phase because the tests require knitr to be
> +    ;; installed. Since it won't (markdown is a dependency of the knitr
> +    ;; package), installation will fail.
> +    (arguments
> +     `(#:phases
> +       (modify-phases %standard-phases
> +         (delete 'check))))

Two things: 1) the comment isn’t very clear.  “Since it won’t” what?  Maybe
you can rephrase.  2) Instead of deleting the “check” phase just write

    (arguments `(#:tests? #f))

> +    (propagated-inputs
> +     `(("r-mime" ,r-mime)))
> +    (home-page "https://github.com/rstudio/markdown")
> +    (synopsis "'Markdown' Rendering for R")

Quoting “Markdown” looks odd.  How about just

    “Markdown rendering library for R”

> +    (description
> +     "Provides R bindings to the 'Sundown' 'Markdown' rendering
> +library (https://github.com/vmg/sundown). 'Markdown' is a plain-text
> +formatting syntax that can be converted to 'XHTML' or other formats.
> +See http://en.wikipedia.org/wiki/Markdown for more information about
> +'Markdown'.")

The quoting looks very odd.  Does this mean that “Sundown” must be
available at runtime in order to use the “r-markdown” package?  If this
is so, shouldn’t a “sundown” package be among the inputs of this
package?

> +    (license license:gpl2)))

This appears to be correct.  The license headers of the files in the “R”
directory only explicitly mention “version 2”, there is no “or later”
clause.  I just wonder what this means for libraries using
“r-markdown”, such as “r-knitr”, which according to your next patch is
supposedly released under “GPLv3+”.  IIUC this cannot be the case.

~~ Ricardo