On 4/22/06, Robin Bate Boerop <[EMAIL PROTECTED]> wrote: > I am having trouble making a type system for my EDSL in Haskell. Can > someone help? A simplified description of my problem follows. > > I have three classes, A, B1, and B2. I want all instances of B1 to > be instances of A. I want all instances of B2 to be instances of A. > None of the classes have methods. > > The following does NOT work, because of a duplicate instance > declaration for A:
I think with GHC, you can use the flag -fallow-overlapping-instances, and for GHCi, there's :set -fallow-overlapping-instances and then :reload. _______________________________________________ Haskell mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell
