[Pkg-haskell-maintainers] Bug#697306: Versioning problem with templates in pandoc binary

[John MacFarlane]

+++ Joachim Breitner [Jan 03 13 21:01 ]:
> Package: pandoc
> Version: 1.9.4.5-2
> Severity: normal
> 
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> Hi,
> 
> currently, the templates are shipped in the pandoc binary package, in a
> path that contains the version number. Now if a program (or source
> package, like xmonad) needs both the pandoc library _and_ the pandoc
> templates, if it depends on "libghc-pandoc-dev, pandoc", it may happen
> that these come from different versions and a program built against the
> former fails to find working templates.
> 
> This occurred in the xmonad build in experimental, where
> libghc-pandoc-dev came from experimental and pandoc from unstable.
> 
> A solution could be a libghc-pandoc-data package that contains the data
> files, i.e. the templates. libghc-pandoc-dev would then depend on a
> compatible version of libghc-pandoc-data. Every package that includes a
> program built with libghc-pandoc-dev (including the pandoc binary
> package itself) copies this dependency.
> 
> This is how it is done in libghc-citeproc; there is some automation
> available there, please check it out for inspiration and copy’n’pasting.
> 
> Greetings,
> Joachim

One note on this:  the templates are not the only data files pandoc
uses.  There are also reference.docx, reference.odt, default.csl,
and files for slides and LaTeXMathML.  See the data-files stanza
of pandoc.cabal for a complete list.

In the development version of pandoc, I've simplified things a bit
by putting all data files in the data/ subdirectory.   That is how
it will be in the next release.

John