T11142.hs:9:49: error: • Expected kind ‘k’, but ‘b’ has kind ‘k0’ because kind variable ‘k’ would escape its scope This (rigid, skolem) kind variable is bound by ‘forall k (a :: k). SameKind a b’ at T11142.hs:9:19-49 • In the second argument of ‘SameKind’, namely ‘b’ In the type signature: foo :: forall b. (forall k (a :: k). SameKind a b) -> ()