PS. compiler change, was: UTF-8 decoding error

22 Sep 2006


      Christian Maeder schrieb:
...
[ 15 of 400] Compiling Data.Generics2.Instances (
syb-generics/Data/Generics2/Instances.hs,
syb-generics/Data/Generics2/Instances.o )
/tmp/ghc5667_0/ghc5667_248.hspp:299:17:
    Couldn't match expected type `forall a1. (Data ctx a1) => c (t a1)'
           against inferred type `c1 (t1 a1)'
      Expected type: (forall a2. (Data ctx a2) => c (t a2))
                     -> Maybe (c [a])
      Inferred type: c1 (t1 a1) -> Maybe (c1 (t' a1))
    In the expression: gcast1
    In the definition of `dataCast1': dataCast1 _ = gcast1
This particular error is fixed by writing:

   dataCast1 _ f = gcast1 f

(for "dataCast1 _ = gcast1")

C.