T15592a.hs:8:22: error:
    • Cannot apply function of kind ‘Proxy j
                                     -> Proxy k -> k2 -> Constraint’
      to visible kind argument ‘j’
    • In the type signature:
        meth1 :: forall z. D @j @k a b z => z -> Proxy '(a, b)
      In the class declaration for ‘D’