tcfail065.hs:29:
A type signature is more polymorphic than the inferred type
- Can't for-all the type variable(s) `aSs'
- in the type `aSs -> X x -> X x'
+ Can't for-all the type variable(s) `aT2'
+ in the type `aT2 -> X x -> X x'
When checking the type signature for `setX'
In the definition for method `setX'