On Wed, 2008-11-26 at 14:30 -0800, Don Stewart wrote:
I think there is a need for a tool like c2hs but that works in a checking mode rather than in a generating mode. It would use much of the same code as c2hs but it would read the C header files and the .hs file (via ghc api) and check that the FFI imports are using the right types. That way it could be run to check a package without the checker tool being needed at build time on every platform. The downside would be that some C header files differ between platforms and c2hs handles this fine while a checker tool might say it's ok on one platform and that may not carry over to another. Still, it would be an improvement on just using raw FFI imports (or hsc2hs, which is really the same thing).
Yes, this plagued xmonad's X11 bindings: almost all bugs in the last 12 months were due to FFI bindings.
I'd love a hsc2hs -Wall mode.
Right, but it cannot be hsc2hs. The model of hsc2hs simply does cannot support such a thing because it does not actually know the C types of anything. It would have to be more on the model of c2hs, using Language.C to work out the C types and then map them to Haskell ones, to check they're the same as the declared types in the .hs files. Duncan