Dear Haskellers, When programming with type functions, I often find myself with a set of invariants that are frequent in my programs and can be expressed as equality constraints on the context of the functions. I wonder if there is any way in current GHC to express some kind of synonyms for equality constraints, to avoid a fixed set of constraints for a smaller expression. The natural way for type classes would be to create a superclass containing all the desired instances class (A a, B a) => C a where {} but as from http://hackage.haskell.org/trac/ghc/ticket/2715, equality constraints are currently not supported in class contexts, what might be reasonable. However, in fact I am just looking for some kind syntactic sugar. Would this be a desired feature for other people? Regards, hugo -- www.di.uminho.pt/~hpacheco