17 Nov
2004
17 Nov
'04
10:42 p.m.
I am using the new existential datatype support (great!) - but now when I patch in fundep support (more or less as I posted before) adding an extra field to ClassD, I have to modify GHC to use the extra field in ClassD... Now when I include a definition: [d| class Test x |] I get the error: ghc-6.3: panic! (the `impossible' happened, GHC version 6.3): deSugar/DsMeta.hs:925:4-41: Irrefutable pattern failed for pattern [elt_ty] Any idea why this might be happening (why is the error in DsMeta, when the TH stuff is in hsSyn/Convert.lhs and typecheck/TcSplice.lhs? Keean.