Hi, While getting hat to work with ghc6 I've come across the following issue: If Bar.hs is this: ----- module Bar where class Bar a where bar :: a -> Bool ----- and Foo.hs is this: ----- module Foo where import qualified Bar data Foo = Foo instance Bar.Bar Foo where bar _ = True ----- then ghc 6.0.1 is happy enough, but nhc98 v1.16 doesn't like bar being used unqualified: $ make clean rm -f *.o *.hi $ make ghc ghc6 -c Bar.hs ghc6 -c Foo.hs $ make clean rm -f *.o *.hi $ make nhc nhc98 -c Bar.hs nhc98 -c Foo.hs ====== Errors when renaming: The identifier bar instantiated at 9:5 does not belong to this class. make: *** [nhc] Error 1 $ If I qualify bar: ----- module Foo where import qualified Bar data Foo = Foo instance Bar.Bar Foo where Bar.bar _ = True ----- then the roles are reversed: $ make clean rm -f *.o *.hi $ make ghc ghc6 -c Bar.hs ghc6 -c Foo.hs Foo.hs:11: Qualified name in function definition: Bar.bar make: *** [ghc] Error 1 $ make clean rm -f *.o *.hi $ make nhc nhc98 -c Bar.hs nhc98 -c Foo.hs $ hugs agrees with GHC 6 on both, and the report seems to agree on the latter (I haven't looked for what it says on the former, but it seems reasonable behaviour). Thanks Ian