[Haskell-cafe] Integrate GHC-API with Cabal

[Imants Cekusins]

cabal-install package includes useful modules. With these modules it is
possible to read the actual build info. These modules could be added to the
Cabal API.

What are the reasons cabal-install can not be added as a project dependency?

Can some modules be moved from cabal-install to Cabal library?



On 25 July 2018 at 11:33, Félix Baylac <felix at alternativebit.fr> wrote:

> Dear cafe,
>
> I am currently working on a project [1] which aims to index the code
> published on
> Stackage in order to provide a "code example" database. Basically, for each
> library,  I want to generate a real-world example corpus for each exported
> symbol.
>
> Before generating this database, I need to retrieve the exported symbol of
> a
> package. So far, I have been gathering the dependencies and integrating
> them in
> the GHC pkg database using an external stack call, I then parse the cabal
> file
>  and load the exposed modules using the GHC API and gather the exported
>  symbols*.
>
> It works pretty reliably on the simple packages, however, I end up with
> some
> missing dynamic flags for some more advanced packages (missing c includes,
> c
> libraries, ASM flags, etc.). I then started to parse and load these
> missing
> attributes to GHC until I stepped back for a moment and realized I was
> re-implementing cabal build.
>
> I then looked for a way to "hook" my GHC API code in cabal build. This
> would
> allow cabal to both handle the dependencies gathering as well as setting
> up the
> correct GHC dyn-flags. The only resource I found was [2]. It's really
> clever,
> however, looks a bit hacky to me.
>
> Is there a better way to perform this kind of  "hook"?
>
>
> [1] https://git.alternativebit.fr/NinjaTrappeur/Exhs
> [2] http://blog.ezyang.com/2017/02/how-to-integrate-ghc-api-
> programs-with-cabal/
>
> * I am aware of the hoogle index generated by haddock. However, this index
> is
>   missing when the haddock documentation of a package cannot be generated.
> _______________________________________________
> Haskell-Cafe mailing list
> To (un)subscribe, modify options or view archives go to:
> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
> Only members subscribed via the mailman list are allowed to post.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/cabal-devel/attachments/20180725/ddf6560a/attachment.html>