Cabal confused about DeriveFunctor

[osaunders]

Full details here:  http://stackoverflow.com/questions/4001749/is-derivefunctor-a-well-recognized-extension-cabal-seems-confused/4001965

[guest]

patch to add DeriveFunctor?, DeriveFoldable?, and DeriveTypeable? extensions

[guest]

I attached a patch to add DeriveFunctor?, DeriveFoldable?, and DeriveTraversable?, but I don't know if I did everything necessary to add the extensions. In particular, the notes in Language.Haskell.Extension.hs say that new extensions should be added to the lists in Distribution.Simple.X.languageExtensions, but (at least for GHC) that seems to be generated dynamically.

[guest]

In the comment for the attached file, s/DeriveTypeable/DeriveTraversable/ . It's correct in the patch.

[duncan]

Replying to guest:

I attached a patch to add DeriveFunctor??, DeriveFoldable??, and DeriveTraversable??, but I don't know if I did everything necessary to add the extensions.

Thanks for the patch, I will ask the GHC devs to look at it, as they are responsible for registering new extensions that GHC implements.

In particular, the notes in Language.Haskell.Extension.hs say that new extensions should be added to the lists in Distribution.Simple.X.languageExtensions, but (at least for GHC) that seems to be generated dynamically.

Right. For newer GHC versions they are generated dynamically. The same is not yet true of other compilers, but I think at the moment only GHC implements these extensions.

[duncan]

Fixed.

Tue Oct 26 23:04:09 BST 2010  Ian Lynagh <igloo@earth.li>
  * Add some more extensions that GHC knows about

[elga]

*  virgin mobile