T7594.hs:37:12: error:
    • Could not deduce (b ~ IO ())
      from the context: (:&:) c0 Real a
        bound by a type expected by the context:
                   forall a. (:&:) c0 Real a => a -> b
        at T7594.hs:37:12-16
      Expected: a -> b
        Actual: a -> IO ()
      ‘b’ is a rigid type variable bound by
        the inferred type of bar2 :: b
        at T7594.hs:37:1-19
    • In the first argument of ‘app’, namely ‘print’
      In the expression: app print q2
      In an equation for ‘bar2’: bar2 = app print q2
    • Relevant bindings include bar2 :: b (bound at T7594.hs:37:1)
    Suggested fix: Consider giving ‘bar2’ a type signature