Hi, On Wed, Jul 25, 2018 at 08:30:48PM +0200, Félix Baylac wrote:

Thanks a lot for this really helpful message.

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I think you might be interrested in one of my packages, [cabal-helper](https://hackage.haskell.org/package/cabal-helper). It's geard more towards editor tooling but I think it should work for your use case too.

Indeed, looks like what I'm looking for.

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Basically you'd have to do `cabal install --only-dependencies && cabal configure && cabal build` for each package you want to inspect and then cabal-helpers API boils down to giving you a list of GHC flags/module names you need to pass into the GHC API to make it work.

(The `cabal build` step is needed to run preprocessors like hsc2hs and compile C dependencies, but once cabal has taken care of that you can usually just load the package without problems.)

I had to make some modifications and jump in some nix hoops to use cabal-install instead of stack to build the packages, but indeed, it does work like a charm.

Ah, I forgot you said you were using Stack. You can use it too if you prefer. You just have to use `stack path --dist-dir` (run in the project directory) to get the path to the dist-dir after running `stack build` instead of using the hardcoded `$PWD/dist` value. There have been some reports of issues with stack using weird combinations of Cabal-library versions though which so it might need some tweaking.

This is perfect, I just tried your library following this example on the text package and it seems to do the job. Thanks a lot, fixing this problem without re-inventing the wheel is a huge relief.

Do you mind if I write a small article on this integration.

No not at all, send me a link when you're done.

It'll probably prevent some other people from using dodgy hacks.

Well I'm not sure I would call cabal-helper not a dodgy hack but at least it's a (sort of) well maintained hack :) --Daniel PS: Looks like I messed up the list-reply on my original message so I resent it and I'm CC'ing haskell-cafe on this one. Sorry about that.