I would like to report something which I think is a bug: Hugs version 1.3 August 1996 Since I did not install it, I do not know the configuration options. OS: Solaris 2 Compiler: gcc Consider the following script: >data T12 a = C1 | C2 a >instance (Show a) => Show (T12 a) where > showsPrec p (C2 c) = showString "This is C2 ".shows c > showsPrec p C1 = showString "This is C1" >data T1 a = C >instance Show (T1 a) where > showsPrec p C = showString "This is C" and the evaluations: ? C This is C ? C2 1 This is C2 1 which is as supposed. But ? C1 ERROR: Cannot find "show" function for: *** expression : C1 *** of type : T12 a seems to be an error, since I have defined a show-instance for C1. Stefan
