Unable to build with ghc 7.7.20131121 about acid-state

[DougBurke]

If I hack around the above, with

#if MIN_VERSION_base(4,7,0)
--import Data.OldTypeable        ( Typeable1 )
--import Data.Typeable           ( gcast1, typeOf1 )
import Data.OldTypeable           ( Typeable1, gcast1, typeOf1 )
#else
import Data.Typeable           ( Typeable1, gcast1, typeOf1 )
#endif

which produces lots of deprecation warnings but does compile, then TemplateHaskell.hs fails to compile, with four messages , stemming from the following change:

src/Data/Acid/TemplateHaskell.hs:260:22:
    Couldn't match expected type ‛m0 Type -> DecQ’
                with actual type ‛Q Dec’
    The function ‛tySynInstD’ is applied to three arguments,
    but its type ‛Name -> TySynEqnQ -> DecQ’ has only two
    In the expression:
      tySynInstD ''MethodResult [structType] (return resultType)
    In the third argument of ‛instanceD’, namely
      ‛[tySynInstD ''MethodResult [structType] (return resultType),
        tySynInstD ''MethodState [structType] (return stateType)]’

[DougBurke]

The following change compiles

#if MIN_VERSION_template_haskell(2,9,0)
                   [ tySynInstD ''MethodResult (tySynEqn [structType] (return resultType))
                   , tySynInstD ''MethodState  (tySynEqn [structType] (return stateType))
#else
                   [ tySynInstD ''MethodResult [structType] (return resultType)
                   , tySynInstD ''MethodState  [structType] (return stateType)
#endif 

but the next error is back to the Typeable changes:

src/Data/Acid/Memory.hs:130:38:
    Could not deduce (Data.OldTypeable.Internal.Typeable1 MemoryState)
      arising from a use of ‛mkAnyState’
    from the context (IsAcidic st)
      bound by the type signature for
                 toAcidState :: IsAcidic st => MemoryState st -> AcidState st
      at src/Data/Acid/Memory.hs:121:16-60
    ...

and at this point I'm not sure my simple hacking is going to fix it.

[cartazio]

GHC 7.8 has polykinded typeable, and TH has some changes in 7.8

point being: typeable1 isn't needed for 7.8. EVERYTHING is typeable. :)

not sure how that deals with the TH problem though

[schell]

I ran into the same problem, but just followed the rabbit down its hole a little deeper. Please review my changes!

[cartazio]

@schell check out my comment :)

[DougBurke]

Thanks for diving that little-bit further down the rabbit hole. This builds for me, and it seems to work when using an Acid Store created with ghc 7.6.3 (although I haven't actually checked to see I'm using any of the API touched by this change).

[DougBurke]

The patch builds for me. Whether it's the 'correct' answer I'll leave for
someone else :-)

Thanks,
Doug
On Nov 26, 2013 11:48 PM, "Carter Tazio Schonwald" [email protected]
wrote:

@schell check out my comment :)

—
Reply to this email directly or view it on GitHub.

[schell]

I'll go back and change those CPP marks and commit again ASAP. :)