blob: 5ccebde83e98439d39750eabb05e8a00605cb6de (
plain)
1
2
3
4
5
6
7
8
9
|
-- The instance decl is illegal without UndecidableInstances
module ShouldFail where
data Rec f = In (f (Rec f))
instance Eq (f (Rec f)) => Eq (Rec f) where
(In x) == (In y) = x == y
|