sig
type ('a, 'b) t = ('a, 'b) Weak_hashtbl.t
val create : 'a Std_internal.Hashtbl.Hashable.t -> ('a, 'b) t
val mem : ('a, 'b) t -> 'a -> bool
val find : ('a, 'b) t -> 'a -> 'b Heap_block.t option
val find_or_add :
('a, 'b) t -> 'a -> default:(unit -> 'b Heap_block.t) -> 'b Heap_block.t
val remove : ('a, 'b) t -> 'a -> unit
val replace : ('a, 'b) t -> key:'a -> data:'b Heap_block.t -> unit
val key_is_using_space : ('a, 'b) t -> 'a -> bool
val reclaim_space_for_keys_with_unused_data : ('a, 'b) t -> unit
val set_run_when_unused_data :
('a, 'b) t -> thread_safe_f:(unit -> unit) -> unit
end