recursive records with weak hashtbl

[Vsevolod Fedorov <sevaAtWork@mail.ru>]

Hello!

I want to define two records referencing each other. First record (A)
has direct reference to second (B) and second (B) has weak hash table to
list records A, which have reference to it. For example (pseudo code):

type a
{
  id : int ;
  mutable field1 : string;
  mutable b : B;
}
type b
{
    id : int;
    mutable field2 : string;
    a_list : Weak-Hashtbl(a);  (* they referenced me *)
}

Is it possible at all?
Is it possible with A and B declarations in separate files?

Any hints and references are welcomed.
Thanks in advance.

Seva