ArrApp arrow arg _ HsHigherOrderApp True)
  = hsep [ppr_lexpr arrow, larrowtt, ppr_lexpr arg]
ppr_expr (H
ppr_expr (HsArrApp arrow arg _ HsHigherOrderApp True)
  = hsep [ppr_lexpr arrow, larrowtt, ppr_lexpr arg]
ppr_expr (HsArrApp arrow arg _ HsHigherOrderApp True)
  = hsep [ppr_lexpr arrow, larrowtt, ppr_lexpr arg]