getSort (Application op _ _) = case op of
            Qual_op_name _ (Op_type _ _ kind _) _ -> Just kind
            _ -> Nothing
getSort (Application op _ _) = case op of
            Qual_op_name _ (Op_type _ _ kind _) _ -> Just kind
            _ -> Nothing
getSort (Application op _ _) = case op of
            Qual_op_name _ (Op_type _ _ kind _) _ -> Just kind
            _ -> Nothing