T19361.hs:6:3: error: [GHC-25897]
    • Couldn't match type ‘m’ with ‘'Many’
        arising from multiplicity of ‘x’
      ‘m’ is a rigid type variable bound by
        the type signature for:
          f :: forall a. a -> a
        at T19361.hs:5:1-14
    • In an equation for ‘f’: f x = g x
    • Relevant bindings include f :: a %m -> a (bound at T19361.hs:6:1)