testsuite/tests/typecheck/should_fail/T8883.stderr


1
2
3
4
5
6
7
8


T8883.hs:20:1: error:
    • Non type-variable argument in the constraint: Functor (PF a)
      (Use FlexibleContexts to permit this)
    • When checking the inferred type
        fold :: forall {a} {b}.
                (Functor (PF a), Regular a) =>
                (PF a b -> b) -> a -> b