method module_expr_get_functor_args =
fun accu ->
function
| Ast.MeFun (_, s, mt, me) ->
o#module_expr_get_functor_args ((s, mt) :: accu) me
| Ast.MeTyc (_, me, mt) ->
((List.rev accu), me, (Some mt))
| me -> ((List.rev accu), me, None)